I'm not sure what kind of creepy crawlies you expect to find in organic soil, but they are mostly microscopic and are not something that can get loose in the grow room, like say fungus gnats (although you may find worms in healthy soil). If you have soil with nasties in it that you think you need to kill, you might want to look for different soil. The reason for cooking is not to get rid of any creepy crawlers or bad things. It is to break down the components and nurture the good microbes.
Basically, I treat mine much like a compost pile. Mix all your components well. I make a super soil that has about 12 different ingredients. You will need to add water. You want it to be slightly damp, but not wet. You will need to turn it about once a week to introduce more oxygen into the mix and keep it from going anaerobic (and icky). I generally let mine go 45-60 days. I usually use kiddie wading pools to mix mine up and let it cook. I use another kiddie pool over the top like a lid. You can use about anything though--trash cans, large totes, a tarp on the ground with another over the top, etc.
I have used raised bed mix from a local garden center that I sat along the side of my shop for a year. I added amendments and it worked great. I would worry about the salt content in composted steer manure. If it works for you keep doing it.
Thanks guys, I'm getting the picture.
Hemp Goddess, thank you again, I really enjoy your replies and the info therein, it really helps that you take the time to break it down so it's easy to follow.
I love this site.