Barrels...
	Scouting...
	Tagging...
	Targeting...
	Upgrades...
	Various Gameplay Tips...

Some machine gun levels feature yellow barrels, usually with enemies nearby. Shoot those barrels, to detonate them and kill nearby enemies. This will result in bonus cash.

After dropping into a zone, use the time where the enemies are not yet alerted to scout the area. The enemy will not be alerted until you fire.

Move your crosshairs over an enemy until it is tagged. Tagged enemies will have a red diamond appear above them, allowing them to be found easier. Tag all enemies before firing your first round.

Headshots will result in bonus money. This will also bypass their body armor when it eventually is used.

Upgrade your sniper rifle as often as possible, followed by your secondary weapons. The final sniper rifle upgrade is the silencer. It allows you to fire without alerting the entire area.

Enemies figure out where you are once you fire after dropping into a zone, but you can use some quiet time ahead of that to conduct a little recon and give yourself an advantage from the start. While you are checking the area for enemies, before you ever fire a first shot, make sure to tag them by letting them pass through your crosshairs. That will make them easier to spot when the action gets frantic. Aim for the head. You won't have to worry about body armor soaking up the damage, and you'll generate extra money. Whenever you can, upgrade your sniper rifle. Once you do so enough, you'll earn the silencer so that you can shoot without enemies figuring out where you are. If you see yellow barrels, shoot them as enemies are nearby. The explosion nets you a bunch of points while also taking out your foes.