TF2 SA Pickup Rule Guideline
Have TF2 experience
You must have played TF2 for a while. If you’re a beginner with TF2 don’t bother joining a pickup. The others will notice it straight away and start moaning about you.
You don’t have to be particularly good at TF2 though. As long as you have a good amount of experience with it (ie. know maps, know where the health/ammo is on maps, know all classes, know all weapons including unlockables, having most of the general achievements).
A rule of thumb is to have at least 40 played hours, and at least 20 hours in two of three of these classes: Scout, Soldier, Demo.
If you have never seen a TF2 clan match or pickup, then you should not join one. That would be like playing a game of chess without knowing the rules – a complete mess. When a pickup starts you can try to join the tf2 server and spectate it. See how it plays out and learn from it. Do it a couple of times and then maybe try to add to a pickup yourself. This is a very important point. If you choose to ignore it you will be banned.