Or maybe this isn't THAT active forum that people would answer to any question in a couple of hours. You have to be patient and you will surely get your answer in couple of days.

Anyway, I think self suggestion or self hypnosis could work. Try to imagine what you want from your dream when you go to sleep. I can't explain it very well but hopefully someone will come and do it. Anyway, remember that the only thing you mess with when you dream is your own mind. I don't think there will be any side effects if you try to decide your dreams with self suggestion/hypnosis.