BatteryTender is what most people use. I've used one on motorcycles for over 30 years. Just plug it in, attach to the battery terminals and forget it. It only charges when the battery drops below a certain voltage. No worries about overcharging.
I have one on my XV, since I have a company car, I sometimes don't use it for a while. I ended up buying a connector such that it runs directly from the battery (thru a fuse) to just near the bottom of the radiator where I can just unplug when I am rdy to use the car rather than popping the hood every time.