There are tons of methods for dream control out there. Search the forum, and just browse through the dream control forum, and you'll find quite a few. Here are some of the most common.

Voice commands are very powerful in dreams, especially when dealing with things like vividness, lucidity, light, etc. If things aren't very vivid, try shouting out "Increase vividness now!" Sounds funny, but its often very succesful.

Dream Spinning is one method of scene changing. First, figure out what scene you want to arrive at. Visualize it and concentrate on it, and start to spin your body. Keep concentrating on the scene, and you should end up there when you stop spinning. If you find yourself in your bedroom, you may still be dreaming, as a lot of people end up in their bedrooms after dream spinning.