In a regular braid there are 3 strands. For this look, all you do is braid one of those strands beforehand and loosen it up with your fingers, then braid as usual. This creates extra texture + breaks up the mundane pattern of a regular braid.
Hair chalking: dampen the strands you want colored, use pastel colors of chalk and rub on the hair strand. Washes out when you shampoo. Also saw where you can fill a bowl with water, put the chalk in to saturate and use gloves to apply wet chalk to hair.