If you're going to have full disclosure, you'd get all your "clients" to admit that there's no such thing as a "psychic," you have no ability to foresee the future, you cannot guarantee any predictions in whole or part, and your services are for entertainment value only.
I realize you may not want to state all this, so you could hire a lawyer to draft a disclaimer that's long and legal enough for none of your customers, who desperately want to believe that there is such a thing as a psychic, to actually read. Then it would be their problem if you disclosed and disclaimed everything and they simply chose to ignore reality and agreed to patronize you anyway.
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You seem to be starting well.
One approach is to consider what can go "wrong" and then provide for it in the contract.
Don't make promises you can't deliver on or use words like "guaranty."
You should find an experienced lawyer who will prepare something for you for a fixed fee, like one hour's time. (Depending on your location that could be from $200 - $400 per hour.)
It is such an unusual business you might find someone you can afford. Make sure your agreement for fees with the lawyer is in writing. Bartering with a lawyer is probably a bad idea.
I remember doing a release for a karate studio. I did it at a reduced rate because I love karate, and for the challenge of figuring out how a sport based on combat can limit its exposure to lawsuits for injury. Maybe you will find the same type of lawyer for your business. Good luck.
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I think Ms. Koslyn has the right perspective. When you have surgery, they tell you that you could die. It happens rarely with routine procedures, so you do it anyway. Tell people that you are actually unable to predict the future, the stock market, or the Superbowl, but you can weave a really mean story and make decent Green Tea. Then if they actually let you separate them from their money after informed consent, you won't be sued.
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