For the belly I line up a bunch of trapezium/trapezoid draggies, flipping them where the belly goes from facing upwards to facing downwards (3). The size should vary along with thickness of the body, of course, but also with the perspective, as you see in the underside of the belly. For my other dragon I used two rows of them, as they were too small in scale. I used the same draggies to make the tip of the tail (still 3). My dragon doesn't actually have a tail tip, but I thought I should do it
Once again, overlap the first rows of scales to make them smaller and give the impression of depth (2) and try to fill the rest up without overlapping too much.
Switch to "under bangs" layer. Start by outlining the sketch you made with diamond draggies (1). Since the dragon has a gradient (even if your dragon is all one color, it's better to use a lighter and a darker shade), you want to use the first color (in this case grey) where it's closer to the belly and the second color (red/pink/that color) where's further apart. Except I wanted the tail to be red/pink/that color, I thought it looked cooler..