The best way is to do a fecal implant with a healthy person's stool. THere is a process you have to go through though to do that, it's written in a medical journal when a gastro treated 7 patients, and he got them to go home to do the fecal implant themselves. It wasn't got candida though, it was for C.Difficile. They were cured of it after they did this because C.Difficile is primarily anti-biotic overuse induced.
After they implanted the alien stool, their flora grew back to healthy.