There are two ways to create the platform for your glow stick archway: cutting it out of cardboard, or using a laser cutter to create an acrylic piece that will hold the ends of the glue sticks firmly in place.
Below are instructions for a cardboard version, which requires only some cardboard, paper, glue, and a good hobby knife.
Download the PDF of the glue stick matrix template by clicking the green button above. Print out the template.
Glue the template to a piece of cardboard.
Press the cardboard+paper under something heavy. Wait 10-15 minutes for glue to dry.
Use a hobby knife to cut out the small holes in the cardboard.
Stay slightly inside the lines to ensure the gluesticks fit tightly in the holes.
Glue NeoPixel Dots
Glue the NeoPixel Dots one by one to the underside of each hole.
Be careful and work slowly! Hot glue is dangerous and will burn your fingertips if you're not careful.
Add Glue Sticks
Once the hot glue has cooled, grab 8 pristine glue sticks and insert the ends of the glue sticks into the top of the holes, pressed them tightly up against the NeoPixel dots.
Clean It Up
If desirable, cut around the outside edge to give the rainbow platform a clean and finished appearance.
On this NeoPixel strip, the red wire is +5V, the middle wire is data, and the other edge wire is ground.
Using alligator clips from the pads on Circuit Playground Express, connect the red wire to Vout, the middle wire to A1, and the edge wire to GND.
To power your NeoPixel Dot strip, just connect a battery to the JST port on Circuit Playground Express and you should see it boot up after a second or two.