My hair is not naturally curly, but I can get a great curly fro with shingling. I've used IC Fantasia (green one), Miss Jessie's Merengue and Kinky Curly Custard. Any gel will do. I part a row in the back and take a piece of hair, put gel on it, and use my thumb and index finger to coat the gel on the hair. Some people have issues with shingling because it's changing your hair to be more curly that it usually is. The pics are small, you might be able to click on them to make them bigger. It's difficult to see my natural hair texture, but it doesn't have natural curl when wet or dry.
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4b is me