First find a good spot on your hat for the circuit. You want the sensor to face the sky, and the piezo to be near your ear.

2-ply thread it easy to stitch with but does have increased resistance over long distances, so we recommend putting FLORA as close as possible to the other components-- behind the ribbon on this sunhat is perfect. Pin it back or temporarily remove it so you can stitch your FLORA. Make sure you can access the USB port!

First use plain thread to tack FLORA to your hat. Use the unused RX pin on one side, and any of the pads on the other side so it doesn't shift around. Hide knots behind the grosgrain ribbon on the inside of the hat.

Twirl the leads of the piezo so they're easier to stitch around with conductive thread.
Thread your needle with an arm's length strand of conductive thread and begin stitching around FLORA's GND pad closest to the battery port (see circuit diagram).

Leave a ~4" tail while sewing, then stitch a few times around the GND pad. Then, at the inside of the hat, tie the working thread and the tail in a double knot. Do not trim tail yet.

Use a running stitch to make your way to the location of the piezo (should be facing down near your ear), and stitch many times around one leg of the piezo. Tie a knot and cut the working thread, leaving a tail.

Repeat to attach the FLORA TX pin to the other leg of the piezo. Pull thread tails taut and apply the tiniest little bit of clear nail polish to the knots. Less is more! Try to avoid getting nail polish in or on the piezo connections, just the knot.

Tug on the knots and allow to dry, then check by tugging again that the nail polish is holding the knot tight before trimming the thread tails short.

You may wish to also stitch the piezo to the hat with plain thread to prevent undo stress on the legs.

Test your piezo by loadign up the mario code from the Wearable Piezo Tones guide.