Beat the eggs together with soy sauce, mirin and sugar with chopsticks.

Heat tamagoyaki pan on a burner. To test if it's hot enough, dip the tips of your chosticks in the egg mix, then draw a line in the pan. If the eggs cook/solidify right away, it's ready.

Pour in enough egg mix to create a thin lining over the pan.

Once the bottom is cooked (the top of the eggs should still be a undercooked to act as a glue,) scrape the sides of the eggs with chopsticks, then flip the egg onto itself lengthwise repeatedly to fold it up.

Move this egg fold to the edge of the pan. Wipe with oiled paper towel, then pour in more egg batter and repeat the process, starting with the egg you just folded, and rolling that up into the new layer.