Hacks/Mods have different patches available. If the patch is .ips, then you'll need Lunar IPS Patcher. If the patch is .ups, then you'll need the UPS Patcher. If the patch download is in .rar, and you can't open or extract it, then download and install WinRAR.
Lunar IPS Steps
Double click the smily red moon thingy.
Click "Apply IPS Patch".
Select the hack's patch.
Select your ROM.
Done! You can now and play the game!
Select the proper folder, depending on your operating system.