What this means is to focus on dealing a SURPLUS of damage. If you take a rail, try to deal more than one rail's worth of damage back (80+ damage). Ideally, deal twice the damage you take. Back up teammates, and over power the enemy by out-numbering them in individual engagements. The team needs to deal more damage than damage taken, and having a numerical advantage is an amazing way to do this. Don't over-extend to chase for kills, even if they're easy- keeping a good position is the best way to deal sure-fire damage without taking lots in return.
2) Play the Map
This means to play good positions, and to use the maps' natural cover and chokepoints. Remind teammates to do this, and to not over-extend. This, however, does NOT mean to camp. It means to hold positions as long as you are doing more damage than you are taking, Reposition when this is not the case- dealing damage on the move is also a great way to keep a damage surplus. Watch out for sneaky rail shots and spam (especially of Rockets, Grenade, and Plasma). This is where chokepoints can be double-edged blades; while it's possible for you to hold off or delay the entire enemy team indefnitely, you can also take, potentially, quadruple damage. So keep your distance when you think spam is coming your way, and always have at least two exit routes. Pin enemy players between yourself and your team- again, keep that damage surplus for the entire team! If someone is trapped between LG and Rockets, they really can't do much.
3) Keep to the Best Possible Strategy
If the enemy is splitting up to flank the team's position, yell out that you are going to attack one particular point. This should be where the fewest enemies are. The whole team needs to rush and punch through the enemy flank, and ideally completely frag everyone in that direction. Then there will be both a damage surplus and a numerical advantage. If they are holding a position that's hard to attack, don't rush in. If nobody takes any damage, it will go to a round draw. This is a boring way to play, but it guarantees that you won't LOSE the round. This means the team as a whole needs to pick fights on its own grounds- and never get forced into having to fight on the enemy's terms. Find their best player and gang up on them. Make sure that they can't deal any damage to you or your team. Strategies do change in the moment, so keep an open mind about the whole situation.
Let's go out there and kill them dead this week, everybody!