Start by making a piece of duct tape fabric. Rip or cut a piece of tape 11 to 12 inches long. Lay it sticky-side down onto your work surface. Cut or rip a second strip of equal-sized tape (you can use the same color or mix it up, like we are doing here). Lay the second piece of tape, sticky-side down, OVERLAPPING the first strip. Make sure to OVERLAP the second piece by at least 1/2 an inch. Continue until you have four strips overlapping each other. (For a larger coin purse, you would overlap more than four strips.)
Once all the strips are together, carefully lift all of Side A and flip it over so the sticky side is facing up. This is now Side B.
Now, rip pieces of tape about 6 inches long and stock them on top of Side B going the opposite direction. Overlap each of the 6 inch strips just as you did on Side A. You should need about 7 strips for Side B. (Don't worry if the edges don't match up. We're going to trim those later.) If you used a pattern on Side A, you can repeat it as we have done, or you can do something entirely different!
Now you should have "duct tape fabric" with some ragged, sticky edges.
Trim your fabric into the coin purse shape. Essentially, you are going to cut out a rectangle with the top side in the shape of a half-circle, roughly 8 1/2 inches long by 4 1/2 inches wide.
Using some more duct tape (it can be the same color, or an accent like the zebra print we chose), cut one piece about 6 inches long. Cut or rip that piece in half so you have two skinny pieces.
With your coin purse in the folded position, place each skinny piece sticking half way on the purse's edges. (It's okay that some of this tape will be sticking off the bottom of the purse, we'll trim it later.)
Now flip your whole purse over so the sticky side of the skinny pieces are facing upward. Fold over the skinny pieces to seal the purse.
With scissors, simply trim of those excess pieces hanging on the bottom.
All that's left are the magnets! Flip your purse back over, so the pocket opening is facing you. Place one of the magnets in the middle of the half-circle shape, the "purse flap."
Rip off a small piece of tape (you can match the color with the tape already on the flap like we did, but you don't have to). Place that piece of tape on top of the magnet to seal it in place.
Now, rip off another piece of small tape. This piece will eventually stick to the OTHER SIDE of the purse, underneath the purse flap, so select your tape color accordingly. Place this piece of tape ON TOP of the magnet you just sealed with the sticky part facing UP. Then place the last magnet on top of the sticky part. This helps you make sure you have the correct polarity for your magnets.
Finally, fold the purse flap over (like you were closing the purse) to set the magnet and tape in place. Wiggle your fingers in between the magnets and secure in place.
Now you've got a durable, sealable purse that you can use every day, or give as a gift!