Gallery: Sushi Week Part 4: How to Make Nigiri Serious Eats
Step 1: Trim fish. You need an extraordinarily sharp knife to cut fish properly. If you've got a yanagi (Japanese sushi/sashimi knife), use it. If not, a very sharp chef's knife will do. Start with a block of fish about 2 inches wide, 2/3 of an inch thick, and 810 inches long. Most sushi/sashimi fishmongers will sell you fish in blocks like this.