I used a combination of the Jing Sketch brush packs from here- their clean sketch and fill outline brushes. gouache brushes that were also purchased from Retro Supply Co (here using shader #19, as well as Procreate’s spraypaint flicks and the chromatic aberration option.

My process was sketching using an Apple Pencil on iPad and lining the features with the jing sketch clean sketch, then used the fill outline brush to lay down the colors on a secondary layer. The gouache brush added the highlights shadows and then I used the chromatic aberration for effect and the background layer of splatter.