It's easier if you have in your mind where you want to go or what you want to see. It also helps if you have been there. And it also helps if you have seen them it recently. And there is the saying "Seeing Is Believing" well in dreams it is "Believing Is Seeing." Basically if you believe it then it will happen. BUt you have to like full on 120% believe not a "I hope this works" sort of thing.