Step 1: Parts and Materials
1) Bike (I'm assuming you already have one...)
2) Christmas Lights - 25' length. Available in your attic, or any local retailer
3) Decorative Light - Star, Angel, anything that glows. Available at your local retailer
4) Lead-Acid battery - 12V, 7AH, from All Electronics:
5) Lighter Jack (optional) - I used a "Y" adapter and just cut off one of the sockets. You can buy a "Y" from All Electronics:
6) Inverter - Just a small ~75W inverter should work, like this one from All Electronics:
7) Crimp terminals - Also available at All Electronics:
Crimp Terminals $2.50
Total Cost: $20-$60
Step 2: Build the Electrical System
The first step is to build the electrical system. This consists of a battery to provide a hefty 12V power source, and the power inverter which boosts the 12V DC up to 120V AC for the Christmas lights.
Begin by selecting a suitable battery - I recommend a sealed lead-acid battery because they are easy to use and very common. Each string of lights draws 1A of current from the battery, so to select the battery size, multiply the number of light strings by how long you want the lights to last. That is the theoretical amp-hour (AH) rating you need for your battery. This is a very basic estimate, actual performance will probably be only 1/2 of the theoretical. I used a 7AH battery and it seems to work pretty good.
The lights themselves do not present a huge load on the inverter, so you should be able to get by with an inexpensive one.
You can hook the inverter directly to the battery, or you can use a lighter socket as I did below. Keep in mind, the tip of the lighter socket is the positive terminal. This should connect to the red + side of the battery. I recommend using crimp connectors to attach to the battery, if you don't have a crimping tool, just solder the connectors or use a pair of vice-grip pliers.
See below for a picture of the finished electrical system:
Step 3: Attach the Electrical System to Your Bike
Step 4: Install the Lights
When it comes to putting lights on forks (the arms that connect to the wheels) pull the lights the length of the fork, wire-tie it at the bottom, then pull it straight back to the frame. See the picture below. If you wrap the forks with lights they could get caught up in the wheels. I only covered the left fork (the one that faces the road as you're riding) to save lights for other parts of the bike.
If you wrap the handlebars, also make sure that you leave enough slack in the wires to allow the handle bars to turn through their full range of motion. I also suggest finding a decorative light such as my star, or an angel, that would typically adorn the top of a Christmas tree. Hang this off the back for added visibility on dark roads.
Step 5: Finished!
Now put on your Santa outfit and spread some holiday cheer!