I like this mini iron for better control with small pieces.
It's important that these traces are as far apart from each other as possible so they don't accidentally trigger each other's capacitive touch sensing. We've tested this particular pattern and it works great; we also made previous versions with traces closer together that did not work well, so keep that in mind if you're designing your own button layout.
Remove the circuit from the embroidery hoop and iron out any creases.