Install the Magellan Content Manager software. You'll soon be greeted with this log-in screen. If you don't have a Magellan Profile, the software will link you to Magellan's Web site where you can register.
Meanwhile, your Magellan software should recognize the device and prompt you to create a device profile and name your RoadMate. By default, the software will suggest the model number, but if you have multiple devices in your household, you'll want to choose something a bit more unique.
Head back to Magellan's Web site and click the tab labeled Maps and Software. You'll be prompted to input you device's model number or supply a serial number. Once done, the site should list any available and compatible map updates.
Select the update that you want to install and you'll be taken to a shopping cart page where you can finalize your purchase. With your purchase approved, you'll receive a link from Magellan that will prompt the map installation via the Content Manager software.