Step 1: Sharpen the Pencil Drawing
I went with the King of the Jungle, and added a mane. This is a little more controlled and deliberate, but don't get too focused...remember that you have an eraser.
Step 2: Ink Over the Pencil
This will give some excitement to the piece.
Step 3: Add Shading
Don't overdo it, the colors will help a lot here as well.
Step 4: Color Your Lion
Next, layer other tones and accent colors.
Step 5: Add a Background
The easily placed perspective lines delivers that effect.