Before you begin, you will need to go to Garmin's website and download their "Web Updater" software.
They are often used to store intermediate turns and intersections that help define a route to a particular destination.
Similar to the waystations used by pony express riders as stopover points waypoints mark significant places on your journey.
More on this you don't have free product lifetime map updates available to you, purchase Garmin street map updates here.
You may purchase street map packs as downloads, or as SD card updates.
The Garmin engineers make improvements in the software all the time.