I really hate paper maps. Never used one. But you can use online mapping. I like RideWithGPS or BikeRouteToaster. You can also use bikely to create a custom cue sheet. You can use the directions to plot your route on one of these websites and download the route for your Garmin, as well as printing a good cue sheet.
I think I'm a fairly savvy computer person, and it took me quite a while to learn how to get my 800 to give me usable, reliable directions. Your 800 will only work for sure for about 10 hours unless you have a backup battery pack. Use a TCX route if you have succeeded in buying an 800 instead of the almost worthless 810. If you don't already have them, I could post the settings that work here.
Yes, a cue sheet in large type in a waterproof cue sheet holder. The best thing that an 800 does, that is after you have figured out how to load a route into it, is to give you a big OFF COURSE warning when you miss a turn. No more having 10 miles added to the course from taking the wrong turn.
Ah, whoops, didn't see your last post that it's an 810. I don't know of a way to load a route into an 810 that will give you turn-by-turn. They're supposedly working on a bug fix, but hey, this Garmin. They don't have to care.