You should go through I-ACT and become certified. Many don't, but with the controversy over colonics, it's a good idea.
As long as you're professional, honest, well trained, and have a genuine desire to help others, I don't think it matters a great deal whether you're male or female. Having said that, I've observed there are more females than males in the business. Creating a good rapport with your clients and establishing trust is what matters. Much of this comes down to your sincerity and your personality.
As a newbie, you would be wise to associate yourself with other established natural health care professionals who share your belief in the value of colon cleansing, which in my opinion, is absolutely necessary when detoxifying or trying to improve or maintain your health. Networking with others is of the utmost value. Doing it on your own is suicidal.
What do you make starting out? That depends. If you're going into this just for the money, forget it. People will see right through you. And...it's a poopy job!
You will have expenses, and until you're well established, you could be in the red for a few months. Plan on it. colonic
machines are expensive. Once paid for, however, they are pretty much free of financial worry. You will need good water purifiers and will have to replace filters every few months (depending on the amount of use, of course). While they are an ongoing expense, make certain you use disposable tubes and speculums, and have a worthy disinfectant on hand. Keep your office clean, clean, clean! You will always have rent and insurance to pay. Don't even think about going into this business without insurance.
Also keep in mind, if you have a heart, there will be those whom you will not allow to pay for the services. That's a financial expense to you, but your soul will be rewarded. Many are on the threshhold of death and are financially depleated. You do what you need to do to help them, even if it costs you something.
Still want to do this? Then go for it! There's a great need.