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!
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).
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.