Once you check in, enjoy the free Wi Fi all over the airport, the huge shopping mall, the smoking areas outside and inside, the observation deck, etc.!
Signage here makes getting around super easy, which is nice. It can be disorienting the first time you land here and the signage just makes everything a little easier.
If you have an afternoon departure on Delta, you'll want to allot extra time to check luggage and clear security. Seems all their flights depart at the same time. Online check-in highly recommended.
Quite a few good dining options and shopping options outside of security. You can shop duty-free and then bring it through security for anything but liquids
Go to the ANA lounge instead of the United one (if you have Gold status or higher). Their lounge is an 8min walk, but well worth it. Better wifi. Made to order udon/soba. Less crowded.
Delta, United and ANA uses this terminal as a hub as a stopover for North America-Asia flights. The terminal ceases all activity by midnight so literally all flights arrive abt the same time.
The cheapest way to go to Tokyo is taking the Tokyo access bus. The ticket counter is Keisei bus seller.You can get a ticket at 900Yen and buses go from 31 bus terminal.