Be the Box
Wall-E is able to transform into box form to blend in with his surroundings. Enemies cannot spot him when he's in this shape so use this trick to avoid some confrontations.
Get Red Crates
If you want to reach a distant red crate, try switching to the first-person view and using the laser. These crates are valuable because they often contain health or laser charges.
Find Explosive Cubes
These cubes are hard to find, but powerful. Available at dispensers dispersed throughout the game, these cubes will blow up already dented doors. You can also use them to easily defeat enemies. The explosive cube has a large blast radius so it can take out many foes at once.
Use Cheat Codes
You can enter cheats at the password screen accessed through the main menu. The codes are a sequence of the robots found in the game. Enter Wall-E, M-O, Auto, M-O to obtain infinite health. To unlock all of the single player levels use the code Auto, ZPM, M-O, Wall-E. For all of the multiplayer maps enter the code Eve, M-O, Wall-E, Auto.