subject: Do's and Don'ts during Self-hypnosis [print this page] Don't make this a one-time affairDon't make this a one-time affair. For the subliminal messages to really get into your subconscious, the hypnosis should not be accomplished at one time only. It's even recommended you do so on a regular basis. Most of the sessions don't last for more than an hour, so it doesn't eat up a lot of your time.