Paint the entire rock green (tip: place a bit of putty on the back of the rock to stick it to your craft surface while painting).

Lightly sketch features onto the rock using a pencil.

Paint on the features with black paint (eyes, nose and mouth).

Fill the eyes in with yellow paint.

Add a red pupil to the eyes.

Allow the paint to dry completely.

Seal with a coat of Mod Podge (optional).