How to make a (retro) romper/playsuit

I've been scouring the net for months trying to find a sewing pattern or tutorial, but till today had no luck. Thanks to Wingmonkey on Youtube my romper obsession can be satisfied. She makes the hottest retro romper I've ever seen! And most importantly she made it out old clothing she had lying around (=my favorite way to DIY since it works out to be free!)