My drawing inspired by Hero's concept.

The making of speed screen recording

Tracing the line-work with the lasso tool and filling (shift + F5) the lasso selections with whatever color

Continuing this process till all areas are covered. This will take a while, but all the hours flatting will translate into saving time in the final coloring stages.

All the areas need to be a different color so I can easily choose the right color in the the final coloring stages.

Final artwork.