Mirror Stage - WIPs/Tutorial

People sometimes ask how I paint, so here's an informal tutorial of my process. I'm not an expert, so this technique should work for people of all skill levels.

1. Do a sketch on its own layer over a flat or gradient background. It doesn't have to be beautiful (mine are usually on the hideous side of the quality scale) but it should give you an idea of where things are going. You can also use a traditional sketch (scanned) for this.
2. Underneath your sketch layer but above your background layer, do an underpainting to block in colours and values. I usually do this with a big fluffy airbrush around ~40-50% opacity and 80% flow to allow a bit of blending.
3. Make a new layer above all the others and begin refining your drawing. I use a basic circle brush with around 80% flow and 20-40% opacity to build up thin layers of shading and colour. You can use other brushes and brush packs if you're good at that. I'm just kind of crappy and spent more time farting around with settings than actually painting.
4. Realize the shading on the hands looks like garbage and redo them from a cellphone photo you took of a mannequin hand at the Bay (your mileage may vary on this step). Otherwise keep refining.
5. Wow it's done. Better put that on the INTERNET.

Finished: