These two posts are the two best resources:

Process overview: https://www.shroomery.org/forums/showflat.php/Number/19792837

More detailed posts on each step: https://www.shroomery.org/forums/showflat.php/Number/17897163

Thread titles of note from the detailed posts (in no particular order):
Dunking the grains: results and discussion
(and on the same topic as ^) Frank's bulk spawning tek (with grain dunk)
How I prepare WBS
My Tub-in-Tub incubator
How I do grain to grain (G2G) in a SAB
My simple coir substrate prep
How to properly pasteurize substrate
Dial in your monotubs like a boss