I print out the complicated junctions of a ride on paper, at large scale, using Open Street Maps. I just use PrintScreen and paste it in to Paint to edit it. The paper maps end up laser printed in monochrome, A4 format and live inside a genuine Ziploc sandwich bag when I'm out on the road. I chuck each sheet in a bin as they become redundant to the ride.
If I'm doing a series of complicated manoeuvres, I have been known to fly down the route on StreetView before setting out. It helps jog your memory when you are out on the road.
I'm not tempted by Garmin yet, and I will confess to carrying a compass sometimes.
Edit: These bags are absolutely brilliant for all kinds of things...