How do I install mods?

[Snickerdoodle11]

So I today I installed Worldbox on my pc and I also downloaded NML. The problem I have is that I am wondering where to store the mod files. Because when I launched the game, I checked the mod menu and it said "Current: Fail"
So I'm just wondering if I was doing something wrong, I to my knowledge have the latest version of Worldbox and NML.