Links
Here are some links that might help you better understand and enjoy Sumo wrestling.
Sumo Terminology. Those of us who enjoy Japanese Sumo often use the Japanese term for various Sumo related words. For example Basho = Tournament, Rikishi = Wrestler, etc. Find more at this site: https://en.wikipedia.org/wiki/Glossary_of_sumo_terms
Here's a great Sumo Youtube channel by Jason with commentary for most of the top bouts each day: https://www.youtube.com/c/jasonsinjapan/videos
bigSUMOfan.com also sponsors some of Jason's contest prizes: 
If you just want to watch all the top Sumo bouts without the ceremony or audio commentary try Kintamayama: https://www.youtube.com/user/Kintamayama/videos
This link takes you to the Japan Sumo Association website English version: http://www.sumo.or.jp/En/
You can find the tournament roster and matches here: http://www.sumo.or.jp/EnHonbashoBanzuke/index/
For those who enjoy podcasts you have to check out Sumo Kaboom 
. They cover the tournaments and so much more. Very entertaining. A new episode most every week even between tournaments.
John Gunning is a sumo sports writer for the Japan Times and an NHK sumo announcer in Japan (not to mention an ex-wrestler) who writes some good articles in English. Find his Japan Times articles here: https://www.japantimes.co.jp/author/john-gunning/
This link by the Japanese NHK channel demonstrates many of the common winning techniques. NHK also broadcasts/streams many of the bouts, sometimes live. https://www3.nhk.or.jp/nhkworld/en/tv/sumo/techniques/
NHK also has some excellent 2 minute videos each focusing on a variety of topics. Highly recommended. NHK Sumopedia
Want to read more in depth about the wrestlers and keep up with Sumo between tournaments? Tachiai.org is a great blog website to give you even more detail and perspectives from some very informed bloggers. You can find them here: https://tachiai.org/
For an insider's view of Sumo in Japan check out this English language translated book from a retired sumo yobidashi called Discover Sumo.
For those who want to follow wrestlers from North America check out NorthAmericanSumo.com You can also follow North American Sumo on Twitter @NorthAmericanS5.
Check out USA Sumo to find information on the annual US Sumo Open held in California in early spring.
Here is a really cool chart by Fred Pinkerton. It shows wrestler movement up and down the banzuke from tournament to tournament.
Enjoy