Teamwork is a core skill, and one of the most important aspects is in the communication between your team members. If the calls are bad or non-existent, then teamwork will fall apart as no-one will know what the others are doing. On the other hand, if there are too many calls it becomes hard to filter out the important information. Player’s can lose focus on their deathmatching if they have to try too hard to decipher calls, or may miss information completely.
Examples of things you should be calling:
– Positions of enemies, and whether they are flanking, jumping, passive, retreating, or powering into you.
– Kritz or uber?
– When, where and which target you are focusing on. Make sure to call their position so a teammate can help you out.
– When a target is low, and how low he is. Also make sure to call their position so your team can follow it up.
– When you rocket jump or play aggressive and leave holes in your defence.
As an example, I’ll list the things I’ll try and call as I get to mid as a scout:
– How I’m approaching mid (depends on the demo and the other scout’s route).
– The positions of the enemy demo and scouts. Will also call if any of those classes are missing (could mean a very aggressive demo jump or a sniper/spy/heavy/pyro).
– Non-standard approaches from the enemy team (badlands valley, granary ramp etc).
– What my intentions are and the outcome of my actions (e.g. defending an aggressive scout in valley, he’s low taken 100 damage, moving on). However you need to be careful not to overcall here, you do not need to call out everything you do, like “hey guys, I’m running around valley”; but just the things that may be important to your team.
– Who’s jumping where from the enemy team. Your teammates may not see the jump so you should call it to give them time to prepare.
The key is cutting out the fluff but still relaying useful information to your team which they can act on. It’s no use muttering to yourself or raging that their medic is on 1hp, this doesn’t help anyone out. Try your best to keep emotions on the backseat and comm calmly. What exactly you call really only comes from experience, but the above should serve as a quick guide to get you started.