Steps for installing
1) Download and install ReShade+SweetFX 2.0 from http://reshade.me/ which goes into your base /Grand Theft Auto V/ folder.
2) Download the Enb dll http://enbdev.com/download_mod_gta5.htm which also goes into your base /Grand Theft Auto V/ folder. (I RECOMMEND TO DOWNLOAD THE FIRST RELEASE OF ENB, I can't get the 0.271 version to work with Reshade)