Making the wristband

Let’s make the wristband for Adafruit Circuit Playground Express!

Duration: ~ 1 hour

Step 1: Creating the wristband for the battery pack

From your piece of paper, measure and cut a strip that is approximately 3 inches x 10 inches. It’s okay if your strip is not exactly 10 inches!

3 x 10 paper

Using duct tape, cover both sides of this strip with tape. Be creative and decorate the strip however you want! If you want to put on more stickers or use glue, make sure you leave enough space on the left side of the strip to attach the velcro. Also, make the rectangle in the middle about 3 inches wide so that you can still attach your battery pack.


After you’re done decorating, paste 2 velcro sqaures or circles to the top and the bottom of the LEFT side of the strip.

velcro on the left

Flip the strip over on the long end. Place the other side of the velcro squares or circles on the RIGHT side of the flipped-over strip.

Flip the strip back over. You should have a strip with 2 pieces of velcro on the LEFT side facing up at you. The velcro on the RIGHT side should NOT be seen unless you flip the strip back over.

Cut a rectangular piece of cardboard that is 4.5 inches long and 2 inches wide. Once again, this doesn’t have to be exact :)

Small cardboard

Lay your battery pack in the center of the cardboard. Your setup should look like this.

Cardboard on battery

Use the shape of the battery pack to form the cardboard - your cardboard should make a U-shape around the battery pack. Here’s a video to show you how to do this!

Using the hot glue gun, attach the two flaps onto the wristband. Leave the battery pack in place. This helps you determine how far apart to glue the flaps so that the battery pack fits snugly into the cardboard.

If you have any scrap cardboard left, cut a small rectangle out so you can glue it to the bottom of your folded cardboard. Here’s a video demonstrating what we did that!

Bottom Cardboard

Your wristband is done now! Let’s get on to making the hand strap for your circuit player.

Finished battery pack

Step 2: Creating the hand strap for Adafruit Circuit Playground Express

Cut a strip of paper that is approximately 2.5 x 9.5 inches.

Hand strap

Fold 3 inches of the paper from the short side in.

Using scissors, on the fold, cut a half circle to a half oval. This creates an opening for your thumb so that you can wear this as a hand strap!

Unfold your paper. You should have a full circle now! If the circle looks too small for your thumb, refold your paper and cut a bigger half circle.


Using duct tape, cover the inside of the circle so that there are no worries about the paper cutting your thumb.

Now, use your duct tape and your creative instincts to finish covering both sides of the strip with duct tape! Remember to leave the thumb hole uncovered from tape.

Take two velcro squares or cicles and paste them on the right side of the thumb hole you just cut.

Flip the strip over on its long side, and paste the opposite sides of the velcro on the left side.

Attach 1 or 2 pieces of velcro on your Adafruit Circuit Playground Express. If your velcro pieces are large, use just 1! If they are smaller, use 2. For this example we attached 2 to our Adafruit Circuit Playground Express.

Place the opposite sides of the velro in the center of your hand strap.

Finished hand strap

Now you’re done creating your wrist and hand strap– good work!

Let’s go ahead and code your game so that you can test out your reaction time.

NEXT: Code