Well, this is how my dad taught me with the potstickers he makes.

1. Start with frozen potstickers
2. In a deep frying pan put in the potstickers and cover them in water, want a bit higher so you can tell when they float
3. High heat. Move them about a bit in case they're stuck to the bottom and you can't tell when they float
4. When they float drain out as much water as you can, put back on burner
5. Add a fair amount of oil, excess water will boil away
6. Fry for a few minutes until the bottom is crispy. Use a spatula to make sure they don't stick to the bottom.
7. Service with soy sauce and vinegar

You have to trust it and I usually mess it up half the time. Sometimes I over boil the potstickers and they fall apart during the frying. I've also flipped the potstickers but it's kind of nice having it crispy on one side and normal on the other sides. Also I've thawed out the potstickers and just fried them but the boiling part is to cook them so that came out a bit raw.