Then all your floors, or mods, are held up by duct tape and gorilla glue much like Skyrim modding except a thousand times more finicky due to the age of the engine.
A modded Fallout: New Vegas is like a tower starting with the base, obviously. This is a complete and thorough guide on how to properly your mod your Fallout: New Vegas, including how to install an ENB. If you have any suggestions, please let us know. We are browsing and trying new mods quite often. This guide is on-going, supported and updated on a regular basis by both creators.