This student has cerebral palsy and since his grasp on a regular crayon is one of those grasps best described as "funky" (see below), this Y-shaped pencil worked fairly well for him.
I want to preface this how-to with the disclaimer that I don't typically use any sort of adaptations or pencil grips for children this young. I prefer to give preschoolers very short crayons and develop their fine motor skills, rather than provide adaptations. With that said, each child is unique, and that's why I adapted this crayon for this particular child.
I used Crayola Air-Dry Clay to form the base of the crayon.
I then placed half of a crayon in the tip of the clay to create this crayon (the air-dry clay takes 1-2 days to dry).