- Find any wall with a corner
- Walk against the corner and push V (or your "step over" key)
- Once you start to go through the wall, try to walk left or right, your character will go in the opposite direction (you'll go left if you press right) and you can noclip
For the wallhack, simply push V against any wall and you'll either view through the wall for 2-3 seconds or you'll can do it unlimited (like in the 2nd clip)