The less time the better. They say you can't be a doormat if you don't lie down. Once you lie down and are a doormat it is hard to change that.
The best chance, in my opinion, for making yourself look like an exciting, desirable guy is to have someone else desiring you. She will not think you are any different until she can see you reflected in someone else's admiring eyes. That's why I think you must at least appear to have another woman interest. Or a group of women. Or a group of men who meet and talk to women. Say you meet a friend or two and go out to a bar or club, and talk to women. That may be enough but she has to believe that there is competition for you. That someone else wants you. Otherwise you are just yesterday's newspaper, waiting to go out with the trash.
