If you want to see a track easily on the Humminbird so that you can follow it, pull up the "Waypoints, Routes and Tracks" menu from the main Nav menu, select the track you want to see and "Edit". Here you can set a line style - solid, dashed etc - and a colour. You can change the style and colour for each saved track (and the current one also, if you want).
I use tracks styled in this way to save common routes - out of a narrow creek mouth for example - in preference to routes, as they don't required extra waypoints. The downside is you can't navigate to a track, but you could get around this by putting a single waypoint at each end if it was needed.
Matt