For starters, I'd recommend choosing a song with a beat that's easy to follow, without too many gimmicks, BPM changes, or too high BPM.

You'll need a mp3 of the song you'd like to map. I've been there before after hearing a song I really enjoyed and wanted to map, so I hope I can provide something to start with and give back to the community that way.

So, you've probably stumbled across the Editor by accident but felt a bit lost, since there's no real guidance, and the choices are all yours.