Well, you can make a series circuit of leds where the sum of the voltage drops add up to about 14 volts or you can make a parallel circuit of leds where each leg of the parallel circuit contained a resistor to consume the voltage that the led does not require. There are many led calculators available to help you do this.
If the led strip is ready made and designed for automotive use (12 volts) and want to install your own switch, just make sure you use a fuse. But be careful, you don't want to drain the battery if you forget to turn off the switch. (You could use a relay that would only allow the switch to activate the circuit if the ignition was in the run position)
If you want a preexisting switch to control the strip to come on at the same time as another light than you would use a relay.
There are many ways you could do this and there are lots of forums that could help you that deal in 12 volt automotive electricity. If you are not sure what you are doing find a friend that could help you. You don't want to make a costly mistake and melt a wiring harness.
Have fun. You will learn a lot by doing this project. Welcome to forum.
Last edited by Lampshade; 04/19/12 10:43 PM.
