L.T.
I don't usually spray mine with anything. I've had mine for a good long time and use it a lot. It's so easy to clean!
As soon as I take off whatever I've cooked and unplugged it, I get 2 paper towels and fold them so they'll fit on the grill, wet them & wring a little so they're not too drippy, lay them in and shut the lid.
After we eat, all I have to do is wipe out the residue -- which usually takes the original paper towels and another one or two. Sometimes, I'll use the dishrag to get under the lip of the grill or on the outside.
Let it air dry and put it away.