When you get 100 adrenaline points, you can activate a combo (aka special move). They expire after a short time and then you have to gather more adrenaline to do another one. If you have an inverse mouse set, you may need to try reversing the order of the commands, ie - instead of Fwd, Fwd, Back, Back try Back, Back, Fwd, Fwd:

Berserk - Forward, Forward, Back, Back
Health Booster - Back, Back, Back, Back
Invisibility - Left, Left, Right, Right
Speed Booster - Forward, Forward, Forward, Forward

Double jump - Jump, then jump again at the top of the first jump.
Double dodge - Double tap Strafe Left or Right, Forward or Backward.
Dodge Jump - Perform dodge, then jump before you land.
Wall Jump - Run along a wall and jump into it. Press jump and opposite strafe when you hit the wall.
Lift Jump - When very close to the top of a lift, jump and you'll get more speed.
Shield Jump - Charge up the primary fire mode of the shield gun, look towards the floor and release. After the kickback, jump again to pull off the shield jump.

Double Dodge and Double Jump can be particularly useful for climbing rocks and slanted walls that might otherwise seem to steep. Simply try double dodging or double jumping forward as you face upwards against the wall or rocks in front of you. You can double jump to get to high areas and jump over large holes and gaps that might otherwise be too long for a single jump to get past. For example, in the Bombing Run game, when you deliver the ball into the ring, you must Double Jump in order to reach the ring barrier and get 7 points. You can shoot it into the ring for 3 points if you wish to score lower but not have to respawn.