I just add a big squirt (about once around the tub) to the cold soak water, let agitate for a bit, stop and let it soak overnight. It's quite amazing the next morning, when all you smell is the bac-out in the washer. I don't add it to hot water because I've heard that kills the enzymes. I also keep a spray bottle diluted with 1/2 water to spray directly onto dipes that may need a little extra help.
I don't add detergent until my hot wash. I do an extra rinse.
Cold soak w/ Bac-out
Hot wash w/ detergent
Extra rinse with vinegar