So I've seen pictures online where girls have their tail fade really well into their tail and it states 'this is done with bubble wrap'
I tried one with bubble wrap, If you don't like painting your skin I suppose this is good for a dry photo shoot for a fabric tail. But otherwise I didn't find the technique that impressive. Here's a tutorial if you want to give it a try;

http://www.youtube.com/watch?v=XJX94ffCb1Y&feature=plcp