Things You'll Need
Instructions
Access the link under Resources to download the Halo "Development Trainer." Save the file to your desktop, then extract it with a utility like WinZip or 7-Zip.
Open the "Halo" program folder from "My Computer." Cut and paste the "Development Trainer" program from your desktop into the "Halo" folder.
Start the "Development Trainer" (but not "Halo"). Click any button to the right of the cheats in the "Development Trainer" to assign cheats to certain keys. Press the key you want to assign the cheat to, then click "Done" to assign the cheat.
Start "Halo" while the "Development Trainer" is still running. Begin the game and hit your previously selected cheat key to freeze time in the game.