From my post "Frustrated and Broke":
When I say Dominant, I'm looking for someone in complete control, who knows what they want, who knows what they want to do, who's comfortable doing so, and most importantly who enjoys being in control and knows it's their natural place to be. A Dominant should control the timing and activities of the entire encounter - not by ignoring the bottom, but by giving the directions, deciding what to do when, how to start, and how to end. Ideally this would be someone who's excited by their dark places, who relishes the permission to tap into their mean streak, and who finds this kind of play powerful and edgy. Someone who knows how to negotiate a BDSM scene and agree upon safewords so they can have the framework to allow them to trust their submissive. Confidence and competence are amazingly sexy.
I also have a particular preferred type - I prefer larger women. Besides always having had a preference for BBW, even for vanilla sex, being sat on by a big ass turns me on.