First thing is to clean - preserving is as much about getting rid of the abrasive stuff (dirt and gunk) as it is about a protective coat. I like to clean the dirt off with Novus no. 2. If you don't have that and don't have the time to wait for it, even Mr Sheen will do a decent job of cleaning, and I suspect the Meguiars cleaner wax will work pretty well too. But to finish the best is a carnuba wax (the hard stuff from a tin) like Mothers California Gold.