Happy Feet
You'll need:
3" thick minicell, about 1' by 1'.
drywall sure-form
thin bread knife (you best cutting tool)
To get the best possible shape, use your Happy Feet to cast a mold. Take out all the air, and jam it into the front of you boat, get in your boat with your planned paddling footwear. Suck all the air out of the Happy Feet and close the valve tight. Now you'll have your shape, trace it onto your foam, give yourself a bit of extra toward your body. The use the sure-form to create the desired shape. Have fun and don't make it too small. It's much easier to take foam off than to add it. Foam is money so don't mess-up or it will cost you.
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