Activating this trainer

If not state otherwise below, press F1 at main menu.
Listen for 'Trainer Activated'.
Press desired hotkey. All hotkeys can be changed on the trainer.

Trainer Options

# Player 
     NumPad1: Super Player
     NumPad2: Unlimited Ammo
     NumPad3: Fly
     NumPad4: No Clip
     NumPad5: Hover Player Higher
     NumPad6: Hover Player Lower
     NumPad7: Increase Player Speed
     NumPad8: Decrease Player Speed
     NumPad9: Set Normal Player Speed
     Multiply: Decrease NPC Speed
     Add: Increase NPC Speed
     Separator: Freeze NPC
     Subtract: Set Normal NPC Speed

# Teleport 
     Decimal: Save Position Slot 1
     Divide: Save Position Slot 2
     F1: Save Position Slot 3
     F2: Save Position Slot 4
     F3: Save Position Slot 5
     F4: Restore Position Slot 1
     F5: Restore Position Slot 2
     F6: Restore Position Slot 3
     F7: Restore Position Slot 4
     F8: Restore Position Slot 5

# Game  
     F9: Game Speed

Notes

For Solo Mode only.

Super Player:
Once on it gives you Unlimited Health and might be other things like Armor.

Unlimited Ammo:
It might effect items too.