PHOTOSHOP CUSTOM BRUSHES
I use as many brushes as I can, and never rely on a single brushpack. Most of the time, I use a mix of brushes by Levi Peterffy, Maciej Kuciara, Jaime Jones, Sergey Kolesov, Luke Mancini and Shaddy Safadi. The best way to learn about brushwork is to change your brushes as often as possible, and try to copy pictures by using any kinds of brushes. For instance, try painting clouds using brushes that you would use to create rocks!