Center the brim upside-down on the hat band. Be sure it is centered before you begin taping, and check periodically during this step to make sure the brim is even. If the hole you cut is too small, now is the time to enlarge it for easy taping.
Apply long strips of tape as shown, first applying them to the brim and stretching them to attach to the inside of the hat band. Tape all around the inside of the brim until you've got a strong hold.
Your hat is now formed and you're ready to close it up.
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