How to make spikes for costume?

Buy some silver fabric. Make fabric cones, leave fabric on the big end of it so it can be sewn onto the costume. Felt would work. Some sturdy fabric would work. Or find some silver spray fabric paint to make it the right colors. .

Make a fabric tube, close the end. Wind it around the cone you have attached to the costume, and attach that to the costume. to make the tube, measure the right width that you want, add a little measure for the seam, sew the seam down the length of it, turn it right side out bu using a small safety pin pinned to one end, take it inside out to the other end. And stuff the tube with old hose, or fiberfill.

Sewing the pieces and then to the costume is preferable. Fabric glue or stapling would work, but fabric glue takes patience to use, and staples catch little fingers.

Bowser Jr Costume

Bowser Shell Backpack

go to Canadian Tire in the auto or bicycle section and purchase the caps used on tires you can paint them silver they don't really need to be pointy get the ones with a dome on it if you get the plastic ones they are easier to glue on ..

http://www.extair.com/image/valparts/valve-caps/do...

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for the washer use garden hose ones and get some silver nail polish to paint all use Krazy glue or some strong glue to keep them all together. place the washer on the fabric glue it down then add the caps and let them dry overnight .

http://www.plumbersurplus.com/images/prod/1/Orbit_...