The most obvious one is someone who looks like a million bucks! If a girl is well put together, fit and always looking her best... she is hard to deny. Makeup, hair, clothing- the whole package.
No one likes a pushover. Men find it extremely hot when a woman knows what she wants and won't settle for anything less than she deserves.
A successful woman that is not dependent on a man for her well being is a true hottie in many eyes. Whether its a job, education or wealth- its hot to know that a woman can hold her own.