A skill you can hone
People speak of "intuition" as a mysterious force that no one can quite explain. Although it turns out that if we look closely enough in the right spots, a lot of what we call "intuition" turns out just to be either a very well-educated guess, or an observation that just doesn't quite break the surface of your conscious mind, and instead has to resort to nibbling at your subconscious.
Developing your own intuition is one of the best skills you can teach yourself. Even if there is sometimes an unknown component (as often seems to be the case), intuition relies heavily on your powers of observation.
Gavin de Becker's famous book on the subject, The Gift of Fear, breaks down this topic in great detail. It has been years since I read the book, but I still vividly remember how, when he went back and carefully questioned witnesses who had experienced flashes of intuition, it turned out that they had been cued in by something. Usually it was something out of place, like the brief flicker of movement in the corner of the victim's eye.
Intuition is often associated with women, but that's just a relic of gender constructs. Men may feel like they have to come up with rational explanations for all of their behavior, whereas women may be more likely to just brush something off as "women's intuition." The truth is that we all have the same capacity for listening to and developing our intuition.
There are a lot of opinions on how you can improve your intuition, particularly since this topic has been co-opted in many respects by the New Age movement. The truth is that your intuition is talking to you all the time; you're probably just tuning it out. (Or it's being drowned in the flood of incoming information that we all have to cope with every day.)
The best thing you can do to improve your intuition is to consciously decide to listen to and heed your own intuition. This can be easier for some people than others, depending on how you relate to your own feelings. Listening to your intuition means paying attention to how you feel about things - about the situation you're in, the person you're talking to, everything down to which line you're in at the grocery store. It also means acting on those feelings, which can be difficult for those of us who sometimes insist on finding rational reasons for our actions.