I was wondering what is your method for giving hints. I find it generally harder than posting full answers (but less tedious, as some trivial points may be omitted), but still I have to write a something like more than half (with respect to details) of a full solution and then reduce it to hints (unless I know the full solution beforehand, e.g. with very simple questions).
Even after that giving a hint is not easy: how to point to right direction and not to give away the full solution? How to not spoil the teaching content behind the question? How to make someone learn rather than "guess the teacher's password"? Finally, from multiple key points, how to pick those suited for the OP? For example, does the OP barely understands the subject and wish only for guide-through, or maybe seeks a deeper understanding and showing a correspondence/analogy to some other theorem is more appropriate?
Any rules of thumb, suggestions, expiriences, hints? ;-)
PS The context is math.SE of course, but it is not limited, if someone wishes to share their teaching experience, I would welcome such posts very much, as those too probably apply here.