Reddit reviews Reality Is Plastic: The Art of Impromptu Hypnosis

Start with Reality is Plastic by Anthony Jacquin. You can also head on over to /r/hypnosis for more resources.

Edit: edited in the link for the book. Happy to answer any other questions you might have.

reality is plastic

and

The New Encyclopedia of Stage Hypnotism

those will give you both a surface level and super in-depth training.

The absolute best I have ever seen is Anthony Galie

watch all his stuff available for routine ideas, method, patter, suggestion cadence...