If you have the hard drive space I recommend making a copy of the game folder as a backup file, it is not a requirement to mod your game but I highly recommend you do so Next make a brand new folder and name it GTA5 Mods and place it where ever you want it, somewhere you will remember, we are going to use this folder to extract downloads to, once you make it, make a new folder inside and name it Backups, then go into the main game folder steamapps/common/Grand Theft Auto V and copy the GTA5.exe and paste it into the new Backups folder.
Start with a clean install of the game if you have modded GTA5 before and I recommend to not install your game in the Programs Files Directory.
