The XDelta patch format is a unique format. It's usually used for Nintendo DS hacks & patches but can be used for other types of patches as well.

Applying the patch is usually very simple. Obtain the original game and drag the file onto part of the patching program. It'll most likely say something like "Drop File Here" or "Patch Applyer". If the right game is dragged onto it, the patch in the folder will be applied to the game and a new game will come out. This new game is the hacked one with the patch applied.

The most common error with this simple patching format is renaming the patch. If you rename the patch file included with the game's download, then XDelta, the patch applyer, won't work properly, and your patching will fail.