Ask HN: How to go from physical prototype to hardware product?

I have made an Arduino prototype that addresses a somewhat niche household use case. I originally made it for fun, but after showing it to some friends who offered to pay money for it without any prompting - I realized I might have a potential business that I would like to explore further. However, I am too embarrassed of how ragtag the device currently is to make more prototypes and sell them (literally held together by tape, string, and a prayer). And I am just a Arduino hobbyist who does not know how to make a more refined product.

Has anyone gone through this process before and have useful advice/guide/readings? Thanks in advance!