How do you create bat wings for Flutterbat?

[Flutterbat]

I need some help trying to figure out how make some wings. Im currently working on a costume based off of Flutterbat and I cant seem to find the right directions to craft them. Here is a picture I found off of Bing.


I could really use some help. If there is a Step-by-Step instructions with some visuals, that would be awesome! Thank you for your help.


Sincerely,

Flutterbat