Bright, glossy hair is always in demand during the summer, but between heat, humidity, chlorine, and sun exposure, the season can also be one of the toughest times to maintain strong strands. So, what does it take to achieve lustrous, hydrated, and polished hair while avoiding dryness, frizz, and oil? Luckily, celebrity hairstylist Travis Ogletree is sharing his golden rules with ET. Travis Ogletree/Instagram The hair expert, whose clients include Shay Mitchell, Lana Del Rey, Miranda Kerr, January Jones and more, is known for creating effortless California-inspired color that looks like it was earned after a long weekend at the beach. But according to Ogletree, maintaining that lived-in look takes more than just sunshine. According to Ogletree, a clean scalp is the foundation of healthy hair, and the key to preventing greasy roots during the warmer months. “Apply conditioner to your ends before you shampoo your hair. Then, make sure you count a full 100 when you massage your scalp. Most of the time, we think we’re washing our hair for a lot longer than we …