Just throw in whatever comes to mind.
1: Crouching when at the end of the corridor allows your allies to keep shooting at the enemy instead of YOU getting shot in the back. Learn it!
2: Prowler makes for a nice long range unit.
3: Don't try to move the scope (as a sniper yourself) against an enemy sniper that has you in their sights. Take cover ASAP! Aim from other another side.
4: Never assume you're safe when your territory is on the front line.
5: Suppressing fire is a good tactic to cause fear. Use it and you can A: Make the enemy think there's more of you and B: have a chance to hit someone poking their head out. Works with both full auto and short bursts (even single shot, depending).
6: Bridges have cover (perhaps more then any damn base in the game, which is disappointing for the bases) use this to your advantage with area of effect weapons. Frag/grenade and clear, don't just rush in. A rule to live by at most times but here more then ever due to the amount of cover and the liner path.
7: C4+flash means suicide vehicle (roll and detonate).
8: Same as 7, only with a willing vic-um... Volunteer. FOR THE REPUBLIC! *Explosion near enemy max*
9: Speaking of which, all it takes is for an enemy max to turn away for one second. I love getting them when their backs are turned.
10: Never stand in the middle of a doorway, it's a sure way to get killed. Cover it from an angle.
Alright, that's enough from me. Time for you lot to chip in.