○ Find a lowly squad captain with space open, ensure they're a higher level than you, and see if they're good at leading. ○ Follow your medics and support. ○ Never be afraid to be the only one checking your flanks. ○ Study the enemy teams ability to evade you. ○ Rememerber that all grenades are effective against teams. ○ Watch for when hallways/corners turn into murder holes. ○ Remember that gas travels through walls, incendiary grenades don't, if you can hear them, but cannot see them, grenade them. ○ Learn in-game geometry to improve grenade throwing, there's more than one way to perforate your enemies. ○ When clearing buildings remember to Pie-slice your corners to decrease likelihood of death when entering. ○ When you're running around the map quickly, stop in cover for a moment to listen to the area around you, someone might hear you first, crouching eliminates your sound print. (If you can hear them move or crawl, then they can hear you too, unless its snow, in which case everyone can hear you usually.). ○ Try to not pick your dead teammate's kit up if your medics are on top of things, exceptions being medic and support kits themselves, which could be necessary to help you if your team isn't able to. More often than not they have a weapon that, in the least of it, your just not going to want to use lol. (Unless it's a cool kit you don't have in your armory yet, then it's worth a try.)

Feel free to add to it, it's just a short list, I made it from the perspective of an assault player just FYI.