During a very fun (and educational) sushi-making class this weekend at Mt. Fuji Sushi Bar & Japanese Cuisine, I asked Joe, our sushi instructor and head sushi chef at Mt. Fuji, about how to avoid faux pas in sushi restaurants. --- Among his suggestions were:
1) DO eat sushi with your fingers (if you'd like). That's the way it's done in Japan.
2) DON'T pile pickled ginger onto your sushi. The ginger is meant to be used as a palate cleanser.
3) DO mix your wasabi and soy sauce together -- that's kosher.
4) DON'T smear wasabi directly onto the sushi; that's gauche.
5) DO put the entire piece of sushi in your mouth; don't bite it in half and put it back onto the plate. Joe said that in Japan, sushi pieces are smaller. They've "grown" here to satisfy super-sized American appetites.
For more tips on sushi etiquette and to learn sushi rolling, I recommend taking a sushi-making class at Mt. Fuji. Joe teaches sushi-making most Sunday evenings at 6:00 PM and the cost is a mere $10 -- and, you get to eat the sushi you make! Plus, it's BYOB.