Fasting is considered to be a good way of detoxing and useful for many shamanic practices, but I don't think this will help trigger projection in itself- I think if you want to force it sleep deprivation may be the way to go- but at the same time I don't think it's a good idea except in very controlled circumstances.
I do think that intent is very important- wanting to do the fasting and meditation and exercises and practices such as affirmation, as said before may help get you in the 'right' 'space' for spiritual fulfillment, projection being one way to do it.