Subliminal recording technique

Hi - I am a newbie and a self-improvement nut.  I have been playing around with creating my own subliminal recordings  I ran across the Southwest Subliminal website and in the description of the process that they use, they indicate that their recordings have 60 - 100 thousand affirmations per one hour recording.  They state that they use multi-tracks, multi-frequencies and tones. I am looking for feedback as to how they accomplish this or any resources that I might look into as to how this can be accomplished.

Thanks in advance for any advice.

chungrdmv