What do you have to do to provide power to an accessory that you want to add to your motorcycle. This is what I did on my R1200RT but the same principle applies to nearly any other motorcycle.
Switched - This means that power is supplied whenever the key is turned on. Power is off when you switch your bike off. It's nice because you don't have to worry about turning stuff on and off.
Unswitched - Power is always available regardless if the bike is running or not. The caution here is that whatever you are powering could drain your battery but there are a number of times you may want to use this method.
Let's say you want to add a heated seat to your bike...
There are two ways you can provide a switched power source to your heated seat. The cheaper (although not as nice or versatile solution) is to power a relay via the marker light wire. The marker light is the small light at the corners of the headlight. FYI: the marker light is really a parking light that is required in some countries. You might be able to use the headlight wire also but I tend to stay away from those because of the CAN bus system. When you turn on the key the light goes on and at the same time it energizes the relay that turn power on for the seat. Bike off and the relay drops power and the seat is no longer receiving power power.
A better solution would be to use a power distribution box. There are several in the market but I use the FuzeBlock.
One small box kills about 4 birds with one stone. This solution allows you have switched and unswitched power available to multiple devices and in addition allows you to fuse each one separately. I use mine to power additional brake lights, XM radio, GPS, power amplifier, and SAE power plug. I also have a direct connected (fused) SAE to the battery for heavy duty stuff.