As a part of a team, you as player has to get your attention on some smaller things, while fighting on the battlefield.
1. NEVER Block a teammate from reversing.
By blocking a teammate in reversing to cover and safety, you can be the reason that this teammate falls, shot either by artillery or other enemy guns. This again will cause that there will be this gun less, later on in the battle fighting against the common enemy, where the firepower of the gun, might could have done the difference between defeat or victory.
2.DON'T EVER Go in front of a teammate, holding still on a spot, pointing his gun in a certain direction.
You have no idea, when the teammate has in mind firing a shot at an enemy. If you go directly in his line of fire, you get the shot, meant for the enemy. Finding this "funny", then this game is NOT the right for you to play.
3.NEVER Go alone.
This rule, is hard even to follow to me. Because I have learned the importance of getting all flanks covered on a map. But going alone, in a direction, and even in a soft armored vehicle, you will be so much eaier to destroy, and by that no assistance to your team.
4. Wise heads, same thoughts.
This one, is a slightly more tip, than a rule. A thing that would be good to keep in mind for you as player. Remember that you are 15 tankers in total. If some of your teammates reaches the same spots as you, then go find another one instead. Even the smallest map, is big enough. Then, if your teammates still follows you, ad driving in a proking kind of way, then leave them. Take screenshots, send those to wargaming, and report those ones, bothering you.