Now as you can see, some cucumber has been placed a small ways from the end of the sheet of seaweed, in preparation for rolling. When you then do is use the mat to start rolling the roll up, starting from the end with the rice. Once the whole thing is rolled, you press on it a little bit to get it nice and secure.
The seaweed starts out all dry and papery, but it absorbs some moisture from the rice and becomes more pliant. Once it's all rolled, you cut it up. Generally one roll like this is cut into 6 pieces. So you would cut it in half, and then cut each half into thirds.
It's best to do the whole rice-roll-cut thing as quickly as possible, because the more moisture the seaweed soaks up, the harder it gets to cut. A sharp knife is paramount. Also, it should be moistened, so that the rice doesn't stick to the blade.
