This is my first tutorial so I will make it like other tutorials I have seen. All credit goes to MrILuziionz.

Things you will need:

Cod Tool and the DVar list:
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(Copy and paste this into your address bar).

Steps:
1. Go on your Call of Duty: World at War and go to single player campaign. Start up any mission and save your game to your hard drive.

2. Now, go to the dashboard, system settings, memory and then go to your hard drive. Go to games, then Call of Duty: World at War and press on the game save. Next, put the game save on your USB drive.

3. Go on your computer and extract your game save to your desktop using USB EXTAFGUI or USB Xplorer; either will work. (If you have Modio, then just explore your device using MODIO).

4. Now that your game save is on your desktop, open up CoD Tool. Go to the advanced menu and open up your game save.

5. Use the DVar list in the description to help you with coding the mods.

6. When you are done modding, rehash and resign, and you're done! Below is the video that I used to learn how to do this.