Started off using Son of a Gun protectant, then switched to Meguiar's Endurance Tire Gel. Meguiar's lasts much longer and resists streaking better. I apply it pretty liberally, and it's quite greasy-looking at first. Let it set a bit, then wipe down with a clean cloth to take some of the shine and any excess off/even it out. After a few days and then a washing it will look its best.