Step 10: Securing, and waterproofing your circuit.
Cut your positive wire from your battery clip to the circuit board, and solder in your SPST switch where you cut the wire. This switch is added so that power is not being run to the 555 timer at all times.
Add a dab of hot glue to the back of your circuit board, and adhere it to your acrylic panel.
Then go through the back of the acrylic panel, and coat all of your LED leads with hot glue as well. This step insulates your wires. If your glue goes anywhere you don't want it to be, you can clean it up with a razor blade or utility knife.
Add another dab of hot glue to the leads on your switch.