"book 4 by Aleister Crowley"
You shouldn't read Liber ABA until you have read Liber vel Jugorum. As far as crowlian yoga goes, Liber vel Jugorum is the first two steps. You don't want to start doing yoga(liber aba is based on yoga) until you've mastered those two or you could potentially go insane like Krishna.
http://www.hermetic.com/crowley/libers/lib3.html
Doing pranayama and the asanas(energy working) come well after you've learned to control your mind, because you don't want energy in places in your mind that could 'activate your mind' when you can't control it properly. It can actually make you quite sick, especially if you are considering the asanas as a means to moving/freeing blood throughout the body.
I'm reading Cosmic Trigger by robert anton wilson. Good book.