Now that I am reasonably happy with the line art, I have begun the masking process. Dropping in the basic areas I need, adding some simple monochrome shading to key areas, and layering things out as efficiently as I can.
The new mouth design puts the 'Mouth Detail' window somewhat out of date, but I will leave it unchanged until i am 100% happy with the way the new head design works.
During this process the order and grouping of the layers are important, as they are constantly altered and adjusted as I work. The worm layers are in one layer folder, the prey item's layers will be in another, allowing me to move them independently to balance the composition as it comes together.