Mix warm rice with sushi vinegar in a bowl using a cutting motion to prepare sushi rice.

In a bowl, beat eggs and mix with salt, potato starch, and water.

Heat a thin layer of salad oil in a pan, pour 1/3 of the egg mixture, and cook on low heat until semi-solid. Flip and cook both sides. Repeat to make 3 thin omelettes.

Arrange the thin omelettes overlapping vertically. Place smoked salmon alternately on top and roll tightly from the bottom.

Place nori on a bamboo mat, spread sushi rice thinly leaving 3cm at the end. Add lettuce and the rolled omelette-salmon mixture, then roll tightly.