The ref photo :

It's a pretty complex one, so the first thing I do is the ugliest and sloppiest sketch possible. It helps dedramatise. Also, if the composition works with potatoes and stickmen, the composition will work with the finished linework

Next, I lined the characters, then the environment on different layers. Usually I don't separate, but here it was easier since the architecture is complex. I used references and my general knowledge of flaming gothic architecture to have something that looks believable. Perspective is tricky, so as long as it looks okay, I’m not overthinking it.

Next, I add shadows. The goal is to have contrast in the important parts of the drawing. It’s also useful for the subtext : here the heroes are bathed in light while the villain is plunged in darkness. Usually I already know where I want the lights and shadows, when I start a drawing.

Then it’s colors. I find it a bit tedious when it's just coloring between the lines, but here there was not a lot of room for variation if I wanted clarity. Here I kept the background white because light was going to be so important, but in general the first step in my coloring is a colored background, to choose colors that go well with the dominant color of the drawing.

At that point, I was fed up so I used a trick to go faster : gradient maps. I used two or three of them, superposed with various opacities, to have that golden glow.

I added some atmospheric light in front of the window, and outlined my characters with a clear color to highlight their shape

I still wasn't completely happy (the middle felt a bit empty), so I added a pillar on the foreground

Then I added the text, and a few other things to integrate it to the image (the top down corner didn't have enough contrast for it to be legible, hence the banners)

Of course I usually don't do things "correctly", my process is more often than not a real mess full of adjusting, especially for the color :D

For different styles, I simply skip entire steps or do things in a different order

Without a line, I tend to carve out details from rough color blocks, usually lighter than the background

For watercolor-like, shadows and intensity comes from layering brushstrokes so it’s very different as a process