I have created my own brush in Photoshop. It's a kind of spackled brush wich adds a nice tecture. I can use this as a colouring brush, smudge brush, dodge and burn. Firstly i always build up my values with a hard brush and end up using my custom brush delicately over my unblended edges. I think of my smudger as my finger, blending as i would with charcoal, and the paint brush like a dry brush adding tiny hints of colour. Always reverting to a limited selection of brushes for blending tends to work well for me keeping things quite natural in application.
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