Most mods will now involve simply dragging files into the models folder or the cleo folder.
Use 7-Zip or WinRAR to extract the folder. Do not place it in your C:\Program Files (x86) directory, as Windows permissions can block mods from writing save data. A folder like C:\Games\GTA_SA is ideal. Grand-Theft-Auto-San-Andreas-Mod-Friendly.7z
A massive project that merges the maps of Vice City, Liberty City, Manhunt, and Bully into one giant San Andreas world. Most mods will now involve simply dragging files