1, Pull your weapon out and press space
2, Stand close to the wall [img1]
3, there is a small spot you can fall down a little bit (your shoes will disappear on the floor), you just need to search [img2]
4, switch into the first person mode
5, lean back
6, press double alt [img3]
7, just leave and rejoin the server
8, and now youre still able do run arround and walk through walls etc... [img4][img5]