 Make teriyaki fish, and then slice or shred into small pieces (make sure all bones are removed), and make sushi rice. Place the cucumber and avocado in bowls. Place the roe in a small bowl, and flavor with finely grated fresh ginger to taste. Cut nori into squares (four squares per sheet) and place on a plate. Put all ingredients on the table with serving spoons and allow everyone to serve ingredients onto their plates to make their own hand rolls. Hand rolls can be made like this, the "right" way, or simply folded over as pictured above. 