#1: CTF is not DM with a grappling hook
CTF is a separate mod because it is a completely different type of game from regular DeathMatching.  DM tactics and playing style will possibly get you more frags than the average CTF players in the game you're playing in, but 90% of the time your team will still end up losing.  If there are enough of you little DM boys on the same team you will end up with some very angry teammates, and some 8 - 0  scores with you on the losing end.  In CTF you MUST play as a team if you want to win.  Read the tips below to find out how.

#2: You must play together and cooperate with your teammates
When someone on your team grabs the enemy's flag and announces that he's running for home, the  things you can do to help the other team the most are:
   a) continue running around aimlessly looking for someone to kill
   b) leave your base as you chase some non-threatening enemy who's retreating
   c) go run and grab all the health/armor/ammo in front of your flag carrier
       before he gets there
   d) wait till all the enemy players leave their base chasing your FC, and then go
       wait where the flag will respawn when they kill him because YOU want to cap it

Remember, the two most important parts of the game are: Defend your flag/base at all costs, and successfully getting the enemy teams flag and bringing it back to your base.  You have to think like a communist to do well at CTF.  Your personal life/possessions are not as important as the success of the team.  You may die constantly because you're putting yourself between your FC and incoming rockets.   You should.  Someone has to for your team to win.  You do not lose points for dying, in CTF, and you only lose 1 point instead of 2 when you fire a rocket at an attacker from 2 feet away and blow yourself up. 

If you have more than 30 rockets and your base is being attacked fiercely, you would be better off dropping your extra rockets for your teammates defending your base to use, rather than charging into the enemy base and dying and losing all of them.  Defense is key to winning this game, and if you are the type of person who refuses to play defense, you better not go in and steal all the armor and ammo from your base and then leave to attack again each time you die.

#3: Communicate and cooperate with your teammates
Yes, I know these last three tips are all the same.  But this concept is very important and too many people just haven't gotten it yet.  Now I'm not saying that you have to follow orders from anyone on your team.  If someone says to "Attack now!" and you see that there is only one person defending your base, it is more intelligent to stay where you are and help defend.  But if you ignore your other teammates completely you are hindering your teams effectiveness.  You should have some macros set up to say important messages to your teammates that are easy to reach while playing.  I suggest (and use) the top row of Fx keys (F1,F2,etc) for these macros.  Use them when it's appropriate.  You should enter them in your AUTOEXEC.CFG file in your CTF directory (folder).  You can have a separate AUTOEXEC.CFG file in your BASEQ2 folder to use for DM games.  I will put my CONFIG.CFG file and AUTOEXEC.CFG file up here in a day or two for you to download and look at for help.

#4: Defense - The Tangible Benefits
When Dave 'Zoid' Kirsch first made CTF for Quake, he (and anyone else involved with its creation) recognized the importance of rewarding Defenders with bonus points for guarding the base.  Thus the idea of Bonus points and "assists" was created. 
   Bonus points are given when you kill an enemy who is in your base near your flag stand, whether the flag is there or not.  When this happens you get the normal 1 point for killing him, plus 1 bonus point.  You also get a bonus point for killing the enemy Flag Carrier, whereever they are, and another one for returning your own flag when they drop it.
   Assists are given when you kill the enemy FC or return the flag, and then your team captures shortly afterwards.  The idea is that your team was ready to cap but needed your flag back, and you made the necessary move to allow your team to cap, so you get rewarded for doing it.

So you can see that by playing defense, your kills can be worth twice as much, and you have the opportunity to get as many extra points as the offensive players who capture the flag do.  For those of you that get off on having the highest score (even though it's still a team game), playing defense is much more profitable.   Rushing into the enemy's base and grabbing the flag while dodging enemy fire is usually more exciting, but you get no points for it if you don't cap it.

#5: Defensive Setup & Strategy  (OBDs and IBDs)
OK, now that I've (hopefully) convinced you to play defense, here are some tips to help you be a better defender.  The object of defense is not only the Flag itself, but your whole base, or in a base with multiple entrances, a clear path from your flag out of your base.  Your team needs to have control over enough health, armor, ammo, and weapons to be able to repel invaders and stay alive to do it again in 20 seconds.   Contrary to what some people think, the best way to defend your flag is NOT to go and stand on the flag itself and aim towards the door.  Most trigger-happy attackers had to fire at people on their way into your base, and will fire a rocket at the flag automatically as they round the corner.  You do not want to be directly in their field of view as they approach their destination.

Your team needs two sets of defenders, an inner base defense and an outer base defense.  Most of the CTF levels have a set a walls that surround the flag itself within your base.  The Outer base defenders are the ones who run around to all the ammo and health and engage enemies as soon as they enter your territory.  Inner Base Defenders stay near the flag itself and should be in a position to kill an attacker just as he gets to the flag or block his exit once he gets the flag.  IBD's play the role of what DM players would call CAMPERS.  They should be in a position to see an incoming attacker before he sees you, and be able to move quickly to stand in the doorway if you don't kill them before they get to the flag.  Otherwise you shouldn't be moving around a whole lot.  You do not want to be running past the doorways constantly because then your element of surprise is lost and the attacker(s) can engage you on a level playing field.  You do not want this; enemies should have a hard time invading your territory, make them pay for insulting your Quake skills!  Make them look stupid by killing them every time they come in your house.  OBD's should follow an attacker all the way to the flag if they get past.  Make them have to dodge rockets from ahead and behind.  Double-team them.  Triple-team them.  Go into a kill frenzy and blow up the ground and all the walls around them if you have to.   But you should never just give up when somebody gets past you and go off looking for an easier target to kill.

The Defensive teams do not have to be static.  Go ahead and switch between IBD and OBD every few minutes if your teammates are getting restless.   Attackers and defenders can switch places too, just as long as the former attacker doesn't decide defense is boring after a few seconds and runs back out of the base again.   There are no set numbers that should be assigned to IBD, OBD, or Offense, because the number/skill of people on a team varies between each game.  Use your own judgement when deciding where to put yourself.  If your team is doing fairly well, and you run to your inner base only to find two defenders already there, go somewhere else.  Conversely, if your base is being attacked constantly and defenders are sending calls for help repeatedly, it's not time to become Rambo and charge into the enemy base.  If your team is playing against a LPB who is ripping people up with rockets all over the place, you can still defeat them with numbers.  Remember, even though you're slower, your rockets hurt just as much as theirs.  You can't hurt your own teammates with your fire, so if a defender and an attacker are going at it 1 on 1, go ahead and launch some rockets into the middle of the fight.  If you get enough of you in there throwing explosives around, they'll have to die eventually no matter how fast they are.

#6: Defensive Tactics  (stayin alive)
Now to actual defensive tactics.  There are a limited number of "good spots" to defend from in each base.  Normally you will not have a big enough team to fill up all of them.  If you do, then you should have no problem killing anyone who enters the area.  But in most cases, the defensive teams will be in an undermanned struggle.  One good way to have one or two people do the work of five is to constantly change positions within your base.  Start out by confronting the enemy just as they reach the edge of your base.  Then after you make a few kills, retreat back into the base and let them make their way cautiously towards your flag, expecting to by jumped on at any second.  Then when they are deeper into your base, someone on your team drops down behind them from his hidden spot up on the wall as the rest of you attack from the front. 

Now most teams won't have enough disciplined members to organize such complex defensive maneuvers, especially in non-clan match situations.  So what can you do as an individual who's playing defense?  Well for starters, move around after killing a few people.  If you notice that you've killed each one of the enemy's attackers from the same position, or if you've killed the same guy more than once in the same way, chances are that the other team is going to be coming after you with a vengence.   All but the stupidest players are going to notice getting killed by suprise in the same spot several times in a row.  Nothing pisses off most quake players more than getting killed multiple times by a stationary camper.  Usually this leads to the victim of the camping trip to go on a personal vendetta against the sniper, often without taking the time to grab armor or extra health.  Since they now know where you are sitting, your element of suprise is gone.  They will grab the rocket launcher, run around the corner and fire at the spot you were sitting without even bothering to look, because they know you're there.  How do you avoid such a painful ending?  By not being there when the rocket hits.  The best choice would be to move to another location that is far enough away that you won't be near the rockets' blast, but close enough that you can still fire upon the spot where they will be shooting from when they attack.  Basically you are anticipating their revenge and when they slip around the corner firing, and they sit there for a second wondering why they didn't just score a frag, you are blasting them from another angle.

#7: Communicate with your teammates and react to what they tell you
A note for all types of macros:  Only hit the macros once in normal situations.  If you are alone on defense and are suddenly attacked by 3 people, then you should hit your "NEED DEFENSE" macro several times to express your sense of urgency.  But if you do this every time you see someone coming towards you, your teammates will start to ignore you and then a fight will break out about not paying attention to team messages.  Especially if Freezer's on Defense... <g>

Offensive Communication

Offensive players should have at least 1 or 2 macros to aid in synchronizing attacks.  One that says something to the effect of "I'm in position and ready to attack", another one that says "Attack Now!", and maybe a 3rd that says "Abort attack, I'm taking fire".  The most effective Offensive techniques are NOT ones based on running into the enemy base as soon as you respawn and attacking anyone you come across along the way.  Organized attacks are 100 times more effective than individual Rambos.  Offensive teams normally consist of 2 or 3 people, and you will usually be up against 3 or more defenders, if it's a good team.  An organized attack will consist of part of the Offense attacking through one entrance, and the rest from a different one.  If there is only one entrance then you will probably have one person enter first and get the attention of the defenders, and then the other(s) enter a few seconds later.  In either case it is important to be able to so "GO" to the other attackers without necessarily seeing them.  We will (hopefully) come up with set attack strategies for each map in practice, so you will not have to have long conversations with your fellow attackers during the match.

Defensive Communication

For organized teams like in clan matches, you should have team macros that send important messages to your fellow defenders.  OBD's and IBD's need to communicate with each other to be effective.  OBD's should be always running around gathering up all the ammo and doing patrol duty.  You should have a key near your movement keys that alerts your team when an enemy has entered your territory.   This lets your IBD's get ready for action and allows any other OBD's to come and help you out.  You can include the %L variable in your macros which will insert your location to help your teammates out in getting to you quicker.   Example:

bind "x" "say_team Attention DEFENSE: Enemy spotted %L"
  This will show up on the screen like this:
((WC)-Player): Attention DEFENSE: Enemy spotted near the Red Chaingun

Since there is usually one of each weapon in each base, it is easy to figure out where your teammate is.  There are a couple of small spots where this feature is a little inaccurate.  For instance, on Q2CTF2 "The Stronghold", one of the narrow hallways that go between the outside area and each inner base are referred to as being "near the Red Railgun" since there are no weapons in that hallway.  (The other hallway has the Chaingun in it)  But as long as you know where these areas are you can usually figure out which one they're talking about.

Communication between Offense and Defense

When someone (probably the flag carrier) asks for "base status", go ahead and answer them.  If you are running around in your base by yourself picking up extra ammo, it is worth it to pause for a second to type "all clear".   Whenever I am hiding or running with the flag and ask for base status several times and get no response, I assume that one of two things is true: either a) there is no one in our base to tell me the answer, or b) whoever is in the base is engaging enemies and is too busy to reply.  Either way, it is not safe for me to return to our base, so I will run around dodging rockets and trying to stay alive until someone says it's ok.   Most other people will probably assume the same thing, if they're smart.  If you're just a lazy ass who doesn't feel like responding even though the base is clear, you could very well cost your team a capture.  You should have a macro that says you are in the base and need help defending, and use it when you really need help.  And when you see this on your screen:
  ((WC)-FRaG GoD): NEED DEFENSE NOW!!
  ((WC)-FRaG GoD): NEED DEFENSE NOW!!
  (WC)-FRaG GoD was utterly destroyed by hOmEbOy's BFG
  hOmEbOy got the RED flag!

You should be pretty certain that FRaG GoD is not just being annoying for the hell of it and probably really does/did need help at the base (note this is a very rare occurrence <g>).  When you see something like this, you should NOT continue to engage in pointless fights with enemy base guards, but run back to your base and try to intercept their FC on his way home.

Another time you should communicate between O and D is on maps where ammo is scarce and/or there are a large number of people playing.  Defenders should announce when they are low on health or out of ammo.  Offenders should also share when they have a lot of extra ammo.  You have greater access to ammo when you respawn in your own base and then run across the middle of the level, compared to staying in your base the whole time, so