Getting more chaotic details
To create more details easily, simply copy parts of your image with the Lasso tool, and turn them around and scale them to generate new shapes. Compare this step with step three. See that new structure on the left? It comes straight from the other one right next to it! I also like to copy the whole image and stretch it a lot, then set the copy layer to Multiply or Screen mode to add a bit of detail to those open spaces.