Start off with a Base Coat :) I personally love this one, it gives me a smooth surface to work on, and it does great protecting your natural Nail :)
Gather your supplies :)
Start off with the outline if the mouth.
Close it together and fill it in.
Add your brown around the mouth.
Get a small paintbrush or Striper
Start with his teeth (he has 4 on top, and bottom)
Add black eyes
White dots inside the eyes
Touch ups on teeth
The creator of this guide has not included tools