Coloring advice

Hi! Happy new year!

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Perhaps someone can help me out here. Does anyone know by any change how to make this effect on coloring or what kind of brushes could I use to get this effect? Thanks!

https://preview.redd.it/nqhelln8k2aa1.jpg?width=1582&format=pjpg&auto=webp&v=enabled&s=86f9f8234ca29954aef491ecbc565a630a453914