Don't Use a Ton of Wasabi
Typically, chefs grate fresh wasabi to-order on the sushi piece. The other stuff is closer to horseradish -- it's super pungent and overpowers the delicacy of the fish."
Don't get scared when the sushi chefs yell in Japanese
We get everyone at the bar and in the kitchen to say 'irasshaimase' really loud when a customer arrives. It's to welcome you and show that they're enthusiastic about you coming into the restaurant."
Don't discount the rice
It's crazy how much time is spent on the rice. Learning how to make it, plus the daily volume, is a real credit and testament to the skill of the sushi chef and how committed they are to excellence.
Don't eat at a place that smells like fish
If it smells like fish, that's the biggest red flag. Fish should smell like the ocean. Bright and clean, like salt water and kelp. Think of a nice beach, those pleasant smells. If the restaurant smells fishy, the fish is either on its way out or already gone.
Don't top your sushi with ginger
The pickled ginger is there for a palate cleanser, not to be eaten with the sushi.
Don't order heavy food early in the meal
Start out lighter, with some sashimi or nigiri pieces. Move on to heavier stuff towards the end of the meal. I want you to eat as many things and experience as many flavors as possible, so if you come in and get a roll and steak special, you're going to be full relatively quickly."
Don't fill your cup with too much soy sauce
You don't want to fill your cup too much -- that's insulting to the sushi chef. Just a touch in there. Whenever you get your sushi, it's been prepared the way that he thinks it should be prepared. His vision. It's meant to be eaten that way. If you feel like you need a little more flavor, just dip a little bit of the piece (fish-side) into the soy sauce. If you dip the rice it'll soak up too much.
Don't be afraid of the Japanese names for fish
If you want to go for the Japanese name, go for it. No one's gonna laugh at you. Sometimes chefs will even flub the names.
Do eat sashimi with chopsticks
Sashimi isn't served on rice or with anything on top of it, so I always eat it with chopsticks.
Do eat it right away
When a sushi chef hands you a piece of fish, the proper thing to do is to eat it right when they give it to you. That's when it's at its peak. The rice is warm and the fat in the fish has been warmed by the sushi chef's hand. It's heartbreaking to see a piece of fish hit the table and sit there for 10 minutes.
Do trust the sushi chef
Order omakase and the chef will craft a menu for you right then, in real-time. They're just doing it on the fly. But be sure to tell them if you're not a fan of certain flavors.
Don't rub chopsticks together
I've never gotten a splinter and I've eaten with plenty of wooden chopsticks. Don't rub your chopsticks together, it's rude. It means that you think that they get poor-quality chopsticks.
Do go outside your comfort zone
Try uni! For some people it's an acquired taste, but it's incredible and there are different levels [of flavor], from funkier to sweet. Another more advanced fish is ankimo, or cooked monkfish liver. If you like liver or foie gras, it's really good stuff. Jellyfish is also absolutely delicious -- when I had it for the first time I was expecting it to be very soft, but it's actually crunchy and reminiscent of cucumbers.
Do trust your eyes
Use your eyes. If the fish doesn't look like a bunch of glistening jewels or the color looks off, like it's oxidizing or turning brown (or even if it just looks super wet and waterlogged), then it's not fresh.
Do pay attention to cleanliness
We clean the restaurant top to bottom a few times a day. It's really important to be as polished as possible. If I walk into a place and it's dirty or disheveled, and they can't be bothered to keep up appearances, then what are they doing with the fish where you can't see?