Seriously...All you need to do, is put a hair dryer on high heat (safer than a heat gun)..>Start at an edge...Heat it up and start peeling. If you can peel straight forward as opposed to lifting away, it is less likely to tear and comes off easier. Just keep the dryer on the section if front of you to warm it up as you work your way across. It will peel off very easily. If you OVER heat it, it will just keep tearing the vinyl as you pull it off.
Afterwards...No need to use anything harsh. Any liquid, or old carnauba wax, has petroleum distillates in it, and will dissolve any small adhesive residue and is totally safe.
Good luck!
DC