Originally Posted by SuddenlyAirship
Well the easiest way I can think of right now would be to buy some light, clear tape, and wrap it around your arm sticky-side up, and then sticky-side down. Basically, make a model of your arm using clear tape and then cut it off. It will be light, fairly transparent and won't bend easily. You can attach it to a simple back harness, and if you want even attach fishing string to the ends so you can make them move. Hope this helped!
Thanks! I used cling wrap as a base on my arms and then used clear packing tape to give it strength to stand up.