Most Helpful Girl
using shampoo in general can cause frizz.
also, if you're brushing your hair wrong (which I did for 15 years lol) it causes frizz. I used one of these since I was a kid link but I only recently found out that I should use a wide-tooth comb. my hair stylist suggests I just use my fingers to brush it, which I've been doing for the past year. it looks really nice now :) and I have REALLY curly and dry hair!
limit shampoo use to 2-3 times a week and brush your hair the right way (which you should google)