Let me look again just to make sure … 
From the male perspective I tend to agree that women seem to like
- confidence
- proper dressing
- intelligence
- humour
It’s not that I’m all these things, certainly not all together and at the same time. However, if I may interject my male take on these, for a man to fullfill all this is not so easy.
With respect to dressing, one of my minor ephiphanies was when I noticed a girl looking at my face, apparently with some interest, then moving south and showing distinct disapproval. I’m quite slender, it had to be my admittedly sloppy dressing (typical geek outfit). Those kind of experiences help to keep us men in line.
That said, it is hard to find out what constitutes dressing well. Girls don’t seem to know that men usually do not speak among themselves about clothes and thereby every man has to find it out for himself. Girls on the other hand are very keen on criticizing each others clothes, with the side-effect that they quickly learn how to dress. I guess men are silent about this to foil the competition.
With respect to humour, that is something that for men is harder to use properly. It is difficult to be humourous if you’re not relaxed, which you are not easily when you’re talking to a stranger. I suspect girls have it easier since they oftentimes can wait for the guy to make a move, then have a reply handy. That, or girls are simply more gifted with humour.
For confidence it is the same thing as with humour: you have to relax to be confident, but you have to be confident to relax. It helps if you feel attractive (proper dressing, just having received a compliment). Maybe the speaking-in-the-mirror trick does help; I’ve never tried it.
The problem with intelligence is that I find I may make stupid-sounding comments. It requires a very intelligent listener to notice the underlying striking brilliance of my remarks. If I’m on a roll, however, appearing intelligent does come naturally. 
I guess there are men who can fulfill those four requirements at will. For us mere mortals it is rather a lot of hard work with varying results at different moments.
And ICP9991, with respect to questions and listening, I’ve found that it helps to try to tone down your own ego a bit, thereby giving her personality more room. Don’t try to show off how much you know, but try to provide a complimentary comment that shows the depth of her own possibly casual remark on some subject. You may directly inquire about things of her personal life, but be careful not to thread on something too intimate. And back off immediately when you notice they do not want to talk about it. There is a fine but distinct line between interest and respect.
If you are really interested in a person, you should not have a problem to come up with questions: you want to know things that complement your image of her as a whole person, such as her family, interests etc. You should not only ask for facts, but also for motivation: why do you like X, what is it that you find amusing in X. Thereby you may actually learn a lot of another person. Then if it doesn’t work out romantically, you may still have found yourself another friend.
On the other hand, you should have some subjects (or anecdotes/stories) on which to speak off the cuff for when there is a lull in the conversation. What I’ve noticed is that if you are really enthousiastic about something, a lot of girls like to listen to that, even if they do not care about the particular subject. I guess it is a certain passion in things.
And above all, you should strive to be sincere in whatever you say or ask.
I should add that I’m still single, though I hope not for too long (don’t ask, I don’t want to jinx it). That’s what all these insights have brought me. 