Walk forward one step, walk back one step, rotate three times to the right, then jump forward, this takes you to the next level.

Many thanks to PHilljr103@aol.com for supplying this cheat!

Step forward, step backward, turn 360° to the left 3 times, then press Alt and backwards to jump backwards to get all weapons

Many thanks to Robert Stone (rdstone@unitedmodel.com) Cooleo1212@aol.com for supplying this cheat!