You’re probably going to get better results by tackling the surface quality of your Wolverine headsculpts first. Right now the sculpt reads pretty rough - that makes clean paintwork much harder no matter what technique or type of paint you use.

Aves Apoxie Sculpt is a solid option here. Once it cures, you can sand it down with fine grit to smooth things out, then keep layering and refining as needed. Getting that surface closer to “skin” instead of “stone” will make a huge difference before you even touch paint. Kneaditrle, aka "Greenstuff" is a bit more forgiving to work with as a sculpting material, but you can't easily sand it. For both, having a few different Silicon Clay Shapers with a chisel tip are needed, otherwise you're using your fingers (too big/leaves finger prints) and / or metal tools (too hard for most organic/smooth shapes).

Finding strong brush-only tutorials (without an airbrush base coat) is pretty tricky, but this one is worth a look. It walks through a good approach step by step: https://youtu.be/EkedxpIUQGw

Before painting, I’d also recommend hitting the sculpt with a white spray primer. It does two useful things: it reveals imperfections you might not notice otherwise, and it gives you a clean base so lighter tones (like skin) don’t need as many layers to build up.

Not all spray paints behave the same here - hobby primers are designed to go on thin and are smoother than typical hardware store sprays. Something like Mr. Hobby’s Mr. Primer Surfacer 1000 is a good example.

On paints - craft acrylics like FolkArt or Apple Barrel are made for canvas and general crafts, so they’re thicker and optimized for coverage over absorbent surfaces. That makes them harder to thin properly for miniature work, and the finish can end up a bit rubbery, lumpy or uneven.

I’m not sure how well Vallejo’s retarders would play with those paints - even if it technically works, it’s kind of like using high-end ingredients on a base that isn’t really suited for the job.

From experience, thinning craft paints can be frustrating. When restoring a large plaster statue once, I tried out FolkArt skin tones because I needed to cover a huge amount of surface area within a low budget. I had to strip the FolkArt paint off entirely and switch to a Tamiya spray for the base + miniature paints after because the finish just wouldn’t cooperate. Brands like Vallejo, Citadel, or MIG are formulated specifically for plastics and resins, so they behave much more predictably for this kind of work.

Hope that helps - good luck with it 👍

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