Step 1: Gather the Materials
A Green LED and a Small Green LED
A Red LED
1 Brwn Blk Brwn 100 ohms Metal film Resistor (small resistors will get too hot and will burn out!)
A Slide switch (on/off)
(Yellow LED optional)
1 1.5 AA battery and battery Clip
1 9 Volt battery and battery clip
Large Altoids Box
Step 2: Make the LED Line
Now match the holes with the PC board and place the leds in the matching holes in the PC board just to make sure they match up with the holes on the altoids box.
Take the PC board with the LEDs in it and solder the leads. Use jumper wire to connect the gaps (or just use a large amount of soder if you don't have any). Now in the middle just after the last LED that's before the red LED, solder a wire about 2 1/2 feet. And do the same on the left (same length), these 2 wires will be the switch on the outside that will make the RED LED turn on for brake. On the left solder a wire about 6 or 7 Centimeters this wire is for the resistor and power PCB. And then on the right solder another wire about the same size.
Step 3: Power and Resistor Conjunction
Take a square of PCB and solder a brwn-blk-brwn resistor (100 Ohms) and take the 6 CM wire from the LED line and solder it to one end of the resistor. Now solder the POSITIVE end of the 9 volt battery clip to the other end of the resistor. Now take the NEGATIVE end of the 9 Volt battery clip and the POSITIVE end of the AA clip and solder it together. Take the NEGATIVE end of the AA battery clip and attach a Slide Switch (See image CIMG2470) and take the very short wire on the RIGHT side of the LED line and solder it to the switch too.
Step 4: Brake Light Switch
Ta Da! Now just get some parts from Ace Hardware to place it on your bike.