Update of an old walkthrough! Im planning on revisiting eyes and hair aswell (although those take longer! Im able to do lips under 5 mins but I cant do that for the rest. LOL)
1. lines 2. base color 3. blend out with skin color (same layer) 4. darker color 5. blend out with base color (same layer) 6. Merge lineart down and blend all together 7. tadah blended 8. Multiply to darken top lip + fixed shape a bit 9. shinies (overlay/luminosity/screen/whatever you want) 10. overlay to saturate 11. Final shinies + touch up with pen tool!