How to oil the valves:
https://www.youtube.com/watch?v=7ro0hgG0bKk
How to buzz on the mouthpiece (this tutorial says “trombone”, but it’s the same mouthpiece as baritone
How to read Bass Clef:
https://www.youtube.com/watch?v=PMk-q5LCiAs
How to play a “D” on baritone
https://www.youtube.com/watch?v=FlCG6JV7AjY
How to play a “C” on the baritone
https://www.youtube.com/watch?v=TEM_OlJImXQ
How to play a “Bb” (aka B flat) on baritone
How to Tongue on the Baritone
https://www.youtube.com/watch?v=X1lUIyULqtA
How to play a “D” on baritone
https://www.youtube.com/watch?v=FlCG6JV7AjY
How to play a “C” on the baritone
https://www.youtube.com/watch?v=TEM_OlJImXQ
How to play a “Bb” (aka B flat) on baritone