Its not hard to do regardless of what people on here are saying. Just make sure you mix your paint properly. Dont get in a rush. If you get a run, or get some dirt in it you just have to buff it out. If you mess it up while buffing, paint it again.
The only kind of paints that are difficult to spray would be single stage metallic paints and candy paint.

 

Very true. It's just paint, it can be fixed. There's not an experienced painter that won't hang a run in something every once in awhile. The best results are achieved with practice, but that doesn't mean you can't get something to be happy with on your first couple tries. Painting your own stuff is always easier than doing it at work IMO because you relax more.