Step 1: Designing It on a Designing Program
I used Inventor because i think thats the best one. First you make a box. For the box u make it 1in high 2 in wide and 4 in long. Then you draw something like the second pic on top of the box. Then extrude it to 1 in
Step 2: Printing Time
Use glow in the dark plastic if you want it to glow. Hook it up with a slicing and printing software like replicatorg. Then you start printing it. Ya your done.