How do I maintain Single Stage Acrylic enamel?

Screw a car cover. Get you one of these from Harbor Freight. Anchor it to the ground and you're done. You can even get sides for them.

10 ft. x 20 ft. Portable Car Canopy
Yep, I bought one, took an afternoon to assemble. You will need a helping hand though. If you do, read the instructions! the bottom horizonal poles go in at the end of the assembly.