To make sushi, first make a rice vinegar and sugar mixture in a 3:1 ratio to mix with cooked rice. Second, rinse rice under running water until clear, then cook it in a saucepan with water for 20 minutes. Third, lay a sheet of nori seaweed on a mat and spread a 1cm layer of hot rice on it, then add thinly sliced fillings and roll it up tightly using the mat. Finally, cut the rolled sushi into pieces using a sharp knife in a single slicing motion.