If you’ve been brainstorming Halloween DIY costume ideas, no need to bang your head on a brick wall. It’s time to put on your thinking cap. Literally! With just a ball cap, squiggles of caulking (the stuff made for sealing tubs, sinks, and windows), and dabs of paint, this bloody brain is yours to wear on fright night.

It’s best to study pictures of the human brain before tackling this project in order to best mimic the brain’s convolution patterns when caulking the cap.

Weighing a little less than a pound and a half, this costume is still lighter than most professional bicycle and motorcycle helmets. Use a cap without an adjuster to ensure a perfect fit.

Project originally posted on CRAFT.