Well before you sell your first book, consider how you want to market yourself. I have a dual career, Young Adult Fiction author and shamanic healer. Before I sold Spell Check (The Teen Wytche Saga #1), I waffled between maintaining two separate websites or finding a way to present both careers on one site. The latter was preferable, but seemed impossible until I realized that the heart of my work was to be a story catcher. Authors catch and translate the stories delivered to them through dreams, inspiration, muses, and observations. Shamans journey between worlds to capture the stories hidden in chakras, past lives, and childhoods. These stories, often flashes or visions, guide the shaman to the source of their client's emotional and/or physical wounds. Thus Story Catcher became part of my brand.
Color is another way to signify your brand. Purple is both a healing color and a color favored by many tweens and teens, readers of my Teen Wytche Saga. Also, I wear a lot of purple. So purple became the signature color of my brand. Themes of karma and empowerment play out in my books and in my healing practice. What initially seemed impossible, a single brand for two diverse careers, blossomed once I concentrated on the similarities between my two careers instead of the differences. You can glimpse the result on http://www.AriellaMoon.com
Author Kristin Wallace, Marry Me, has written an excellent How-To article, "Brand Smart - Your Guide to Creating Your Author Brand." http://savvyauthors.com/blog/index.php/brand-smart-your-guide-to-creating-your-author-brand-by-kristin-wallace/