How does a navigation device work?

There are many devices which you can use for navigation. We need more info about the device to be able to give you an exact answer. I suggest you search the device you own and search it's manuals. But most navigating devices are easy to use. They basically will recognize your location and it'll ask you to set up date/time and such. At last, you'll just have to introduce the address you wish you drive to.

Let the satellites be your guide. GPS - Global Positioning System -- uses satellites to track and direct you.