Your two bottom pieces should fit together like this. Next, cut two pieces of the 3" stock at 10" with a 15 degree angle on one end. Then you can trace out the light sabre holder outline from the provided PDF pattern.
Next, draw your outline on the 2 pieces of wood. Make sure the angled part is on the bottom and cut out the pattern. Then, pre-drill 2 holes on the bottom of each piece where the angle is, about 3/8" up.
Now, you should have something that looks like this. Put the 2 pieces together. I had to mark the center because I used a biscuit joiner. You can obviously use other methods of joinery such as screws, dowels, or some good glue.