My church actually holds classes where everyone brings in piles of old magazines and they do this together, only they call it Treasure Mapping. I did one once, but it made little difference.
I agree with Hermes.V that it depends on your natural way of perceiving things. I am a very visual person already, so adding the board with photos of all my wishes did not make much difference, since I already picture things in my mind a lot. If you are not so visually oriented, it may help a lot.
Using affirmations and taking actions that will help things to happen are, of course, needed too. There have to be more thoughts that favor your desired outcome than otherwise. That can be really, really hard, since the brain is wired to focus on negativity, so give yourself a break and some time to work on it.