Wow! I really thought you just bought gyoza wrappers but you actually made them from scratch! That's so incredible!
The way I usually cook gyozas is to put water on it and cover, and just wait til it's crispy on the one side. Some people put water, cover and when the water is gone, they add oil to it. Yours is also a bit different! There are just too many ways to cook gyozas.. Oh no, just thinking of it makes me want to have gyozas for dinner. 😅