After reading Robert Waggoner's book "Lucid Dreaming: Gateway to the Inner Self" I'm convinced there is an awareness, or inner ego, behind the dream, more powerful and knowledgeable than we can ever understand. That awareness will often answer to your desires if you wish for it in a mannered way. If the dream seems unclear and unstable, ask for clarity and stability. You can either ask a dream character, or the more preferred way of asking the dream itself by just shouting out.
In fact, you can ask the dream anything you wish, and in most cases the awareness will respond in some way.