JonathanMcEntire

I've been playing video games for as long as I can remember but it wasn't until recently I started getting into mods. While I was trying to get a body replacer for Oblivion a question came up. How am I supposed to install mods without getting all the files mixed up? What if I want to remove those files later? How will I know what's what? I'm a noob at modding. Any help would be appreciated. Thanks.