I remember Natalie DIYed some waxed denim but that the wax ended up a little stciky - I came across this video with an alternate technique that should dry down all the way. The downside is that it involves paint to match your denim - so if you want to wax printed denim perhaps just use the gel they recommmend?

http://www.fabsugar.com/DIY-Ho.....C+Need.%29