Any tips from your experience when you started?
Edit: Based in California, USA. All infrastructure located in California as well.
I have heard of https://paddle.com/ , which is a payment service + tax handling. Basically it's like apple's app store. You sell your creation to paddle, and they resell it. So they will handle taxing and you get royalty. it's way easier.
I have never tried them, but if I were to create a side-hustle, I will consider paddle.