Keep them cooking on one side until you see the first spot of brown, and use the spoons to flip them. Some potstickers will need to be flipped three times, some only twice - it depends on their shape. if you point the shell-shaped ones away from you, you can avoid the worst of any flying oil they may spit up. I like to start two pans going at once, to get the cooking done faster and keep me on my toes.