Tachinomi rules nobody tells you

Standing bars look intimidating from outside because you can't see in. Here's what I wish someone had told me the first time.

You usually pay as you go, not at the end. Order, they put the drink down, you put money on the counter. Some places have a tray for it.

There's no table charge, which is the whole point. That's why locals do two or three in a night instead of settling in at one.

Don't take a big bag. There's nowhere to put it and you'll spend the hour apologising to people squeezing past you. I learned this with a backpack in Ueno.

Staying about 45 minutes is normal. Staying three hours is not rude, but you'll notice you're the only one doing it.

Most places I go have no English menu. Pointing works fine.