The easy answer is you pray for help, guidance or direction. And yet that is not an easy thing to do. As a Wiccan/Pagan do you pray to the goddess? If you're faced with a trying situation, what do you do next? And how?
I used to dream I was falling down some pit or off a cliff. I would wake up with a start. I was told recently that those dreams are of the heart stopping and it's the body's way of telling you to BREATHE!! So sometimes we have a natural way of dealing with a situation.
Can you put faith into something you can't see? With God you have to. Just as you know on a cloudy that the sun is really up and shining, although you can't see it you still have evidence to support your understanding. So it is with those who have a belief in God. There is evidence that in everything we see and also things we can't see, the Creator is there. The only fly in the ointment is that man has done a monumental muck-up of this earth in that he is killing it, and mostly in the name of science.
How do we know a demon isn't answering instead of God? That's not so easy to pinpoint. Knowing something is one thing, but knowing it accurately is a totally different ball game. So accurate knowledge of God helps the seeker to understand what God likes, dislikes, supports or dismisses. Then our prayers can be targeted into specifics rather than generalisations. Prayer is useful for calming the body in times of stress which can be a good thing. Being stressed or wound up or easily angered does no good to the body at all. It all has to have an effect sometime and somewhere and usually does.
The answers to the majority of our questions are to be found quite easily. Where faith comes into play is will we accept that what we dismiss is actually the thing we really need?