Prepare:
-Slice vegetables lengthwise; carrot and cucumber are the usual culprits. A normal addition in Korea, but you will need to buy in a specialty store in the States, is 단무지 (danmuji): sweet pickled turnip
-Prepare anything else that you think you'd like: meat such as steak, chicken, pork, or any ground meat work well; avocado is great, as is cheese.... have everything prepared so it's long and thin
Cook:
-Cook rice: about half a cup per sheet of seaweed, with a little more water than normal so it's a bit soggy - preferably medium-grain or "sushi rice". Once the rice is cooked, mix it with about 1-2 pinches of salt, 2 tsp of sesame oil, 1 tbsp of soy sauce, and some sesame seeds
-Place a sheet of seaweed on a flat, hard surface, shiny side down
-Put about a handful of rice on one half of the seaweed, spread out evenly
Tips:
-If you want tuna (which is very popular in Korea) you should mix it with a little mayonnaise and, though I don't know if you can find it in the States, some perilla.
-This stuff doesn't last very well - one day tops. So eat it right away.