If you're interested in dating a womaniser, you should be prepared for a long and possibly difficult road to commitment. A man who has a reputation as a womaniser needs to be approached much differently than other men. Since he typically stays interested only if there is a chase, it's important to always keep him on his toes and to require him to pursue you, instead of the other way around.
Refuse his offers for dates in the beginning. A womaniser typically is motivated by the challenge of getting a woman to pay attention to him. The longer you can ignore his advances while still giving him the slight hope you may eventually go out with him, the harder he will try.
Don't ask about his other girlfriends or if he is seeing someone else. The key to keeping his attention is to pretend you aren't that concerned about the other women in his life. It will be a refreshing change for him, since many women he dates probably get possessive and jealous.
See him only once or twice a week. Do not be available to him whenever he calls or asks you out. He will not be motivated to commit to you if he thinks you are willing to drop everything for him. Maintain your own interests and live your own life.
Avoid physical intimacy with him for as long as possible. Let him know that you enjoy his company, but you're not going to get intimate with anyone unless that person is able to commit to a relationship. Don't make it sound threatening - simply state that it's your preference to wait for a commitment from the right man. By not saying that you're waiting for a commitment from "him," it leads him to believe there may be other men in your life with whom he has to compete.
Date other men or see them casually as friends. Keep your options open. This shows a womaniser that you're a desirable person and that other men want your company. From time to time, tell him that you have plans with someone when he asks you out. Don't mention whether it's a guy or a girl. Not knowing is enough to make a womaniser motivated to keep you.
Show him your strong side. Womanisers typically don't like females who will bend to all their wishes. They enjoy a challenge. Show him you are not someone to be messed with, and point out when he's treating you unfairly or with a lack of respect.