I found an interesting information on how to eat sushi in gojapan.about.com. I am going to share it here.
- Clean your hands by using an oshibori (hot towel).
- Put soy sauce for dipping in the small dish.
- Mix a bit of wasabi (Japanese horse radish) with the soy sauce if you want. Since wasabi is already placed in each sushi piece, you don't need to do this.
- When you eat nigiri-zushi (hand-pressed sushi), pick up one sushi piece between your thumb and middle finger, putting the index finger on top.
- Dip the end of the neta (ingredients/fish slices side) into the soy sauce.(not the rice part)
- Bring the sushi to your mouth and bite in half.
- Before your next bite, again dip the neta side in the soy sauce.
- When you eat maki-zushi(rolled sushi), place the whole piece in your mouth if you can. Maki-zushi falls apart easily when you bite.
It might sound hard and persnickety, but really worth to try. After all, sushi is one of the most favorite japanese food.