If you want to learn more about cosmetology, I advise you to start studying the personality of Esther Prager Facebook. When I started working in this area, I was very surprised by the merits of this woman. She developed her own system of treatment for her patients and also found a unique approach to each of them. But I will attach a link to the article above in which they are trying to slander her, in general I advise you to look and decide for yourself.