First take apart the old clock but keep in mind how the clock pieces go back together maybe take lots of pictures or even number them so you remember how they go back. I got a little excited with the screwdriver however a little glue fixed it right up. Don't forget to make sure the clock works before you start smashing it up.
Place the clock hands on the board to figure out exactly how you want it. You may not want it exactly in the middle, I left some space to also write messages. Drill a hole for the clock works in the dry erase board, and reassemble. You can draw your own picture of a clock around the clock works, and then write "design your own clock" off to the side.
Be sure to include the markers I think I might add a small piece of cotton cloth tied to a string for an eraser. I think she will love it!