How can I cure candidas overgrowth on my own?

No such thing. There is no such thing as candida overgrowth, no matter what you might read on the web.
It's a myth. Dr. Galant is correct. This is a scam. If you buy into the idea that your body is colonized by this common fungus and that it's making you sick, you will never feel well again. Instead, you'll continue buying various remedies, none of which will ever make you feel better, and you'll also tend to neglect real physical health problems that we might actually be able to help.