I'm surprised there isn't a gnoll listing in the species. I'll just use Hyena for the moment.

I've never drawn a gnoll before. Any time I need to approach a species for the first time, I'll grab a bunch of images of styles and designs I like, then draw from those with ideas and features that help define what a gnoll would be. What makes it a gnoll and not a hyena? Shape, posture, features that are prominant or diminished. I write up the notes to help me determine what it is and with luck, help me to reproduce this later.

When I go to try drawing this for a species pic or commission, no doubt it will look nothing like this, but I have a base to work from! (And then wildly go a different direction)

Species study by ME!