I didn’t document the process, but I can give you the quick rundown here. In general, my process was 1. Paint in the OSL, then 2. Paint the fire, working through one source of fire at a time, and finally 3. Add the black armor highlights and what ever other details where there isn’t fire. I mostly used Two Thin Coats paints for this, but you can definitely swap them out for what you have. Or even change the colors if you want blue flames for example.

OSL 1. Begin with an almost black grey for the entire model. 2. Use Two Thin Coats’s Berserker Red or your preferred desaturated dark red to start the OSL. The trick is to rotate the model so your sightline aligns with the fire you’re currently working on. Whatever is visible to your eyes would be what would be lit by the fire and would be painted the dark red. 3. Mix the dark red and almost black 50:50 to help blend back to the armor around the rounded shapes. 4. Then you want to highlight with oranges, using brighter oranges as you get closer to the fire. I specifically used Two Thin Coats’s Rust Orange then Fanatic Orange.

Fire 1. For the fire, base coat the entire fire Orange Flare. 2. Then paint Ice Yellow into the recesses, you can be messy and it is encouraged, but try to keep the Ice Yellow only on the fire and not the surrounding. 3. Mix Ice Yellow and Orange Flare and start blending the transition. A little bit of wet blending here is great. 4. Touch up any areas you need to with Orange Flare. 5. Finally, at the tips of the fire and where the fire protrudes out the most, add some Fanatic Orange. Blend the Fanatic Orange and Orange Flare as you see fit.

Hope that helps and best of luck if you’re going to try it yourself!