Hmn....Well, excluding the idea that you could use a lot of paint to paint your body XD;
you could get a black shirt, put some tape that won't leave residue on the shirt really well(That means really covering the area well so spray won't get on other parts of teh shirt) around the area you need white, and try spray painting it white or preferably using fabric paint. THen after that from the neck up (Because the headband will cover the shirt collar it looks like) you can just paint your face with non-toxic face paint! I've had luck with that sort of thing a lot of times
You can use fabric paint on some black gloves since they don't have much anyways X3;
I hope this helped and I hope to see you there! :3