I know the secret to dream incubation....

(Okay maybe it doesn't work for everyone, but it works fantastic for me)
It is known that we often associate strong images with music, and it is known that the ideas we think of when we fall asleep or wake usually stay with us quite well. Put a and b together and you get:
Listen to music as you fall asleep, think of a really strong image and you will likely have a dream about it.
The music has to be soft enough to fall asleep with and a memorable tune, I like to use oriental soundtrack music. Just think of the scene you want as you fall asleep and it might work. I've been using it for a while now and I gotta say it works a hell of a lot better than incubation by chance (in fact it never worked for me by chance

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