i keep forgetting to say this but you have one of my fave art styles ever. not even like just within the fandom or whatever, just overall. i love it terribly i savour it like fancy dessert
SSSTTTOPP you've got me blushing and kicking my feet hgeheuehehehee
start with grayscale because colors are too hard. my process was really just lasso tool the area you want to work on, lightly airbrush for a gradient and then use a darker gray to work on details. honestly i don't know what i'm saying, just remember to stay loose when rendering and that although it looks like crap things ARE going to get better in the end hopefully.
okay uhh then start using blending modes overtop to color. i used modes like overlay and linear light and uhhh like basically look at what falls under the contrast category in ibis pain. those all work well. no specific blend mode to use, just pick whatever looks nicest to you. use airbrush to color overtop. okay around with hue and saturation and opacity and blend mode and color curves and oh you're done i'm so sorry i don't know how to explain i didn't realise i'd would be so hard