To be successful with any self-hypnosis project, visualizing what you desire to create or change is essential. 

Visualize your success.  If you want to lose weight, visualize yourself as a slimmer, trimmer version of yourself.  Always visualize the end result.  If you want to be more confident, you might first want to get into the feeling of confidence by remembering what it feels like to be confident in a given situation.  Then you would want to take that feeling of confidence with you as you visualize yourself being confident in whatever situation you choose.  It's extremely important to bring a sense of confidence and faith into your visualizations.  See the end result as if it has already occurred.  And make your visualization as real as possible.  The more you envision your success, the more likely you are to succeed.

More hypnosis techniques:

Eye Catalepsy

Eye Fixation

Staircase Technique

Metaphors

Fractional Relaxation

Conversational Hypnosis

Indirect Suggestions

Double Bind

Guided Imagery

Visualization

Post-Hypnotic Suggestions

Direct Suggestions

Confusion Technique

Tongue Relaxation