Try to figure it out by myself, but on some occasions I like to ask my father for his opinion...doesn't necessarilly mean, that I agree with him and follow his advice, but it never hurts to get a different point of view on certain things, if you want to make a good decision. Other than that, maybe a friend, if I thought he might have experience in that area and could provide helpful insight or I might even ask my sister for advice if it was some medical issue...pretty much depends on the subject I'd like to get input on.
But it's just to gather information, in the end I must feel comfortable with the decision I'm going to make, so nobody else is going to make the decision for me.