Watching Sumo at the Ryogoku Kokugikan, timetable and a guide on seating

What kind of seats are available and at what time should I be there?
Your questions answered on this guide to watching a sumo tournament in Tokyo, held for 15 days in January, May and September.

0:31 Approaching the Kokugikan (1pm)
1:15 Type of seating
2:46 Juryo division matches (230pm)
3:37 Makuuchi top division wrestlers (340pm)
4:37 Appearance of the YOKOZUNA (355pm)
8:25 Final match of the day (550pm)
12:25 Yumitorishiki closing ceremony (555pm)

(Update 2023)
Much of the scenes here were shot at the Kokugikan during a tournament in late 2020 when there was restriction on the number of fans allowed. Now all seats are sold like before and the tickets do tend to sell out, especially for Saturdays and Sundays.