Fuel- premium, mixed with a quality oil. most people run 32-1 or 40-1
First thing to do- replace the stock air filter set up, they tend to suck in dirt.
After the ride- wash it, grease all the fittings, clean air filter, check for any loose parts, check fluid levels.
Storage- depending on how long it is being stored, mine usually sits all winter. I fog the motor, drain the fuel tank & the carb, seal off the airbox & plug the silencers, change the coolant & trans oil, & prop it up on a stand to take the weight off the suspension.