You know the Buddhist proverb, "With our thoughts we make the world?" It might be more accurately said, "With our feelings we make the world." There's no better way to manifest than to get in that good feeling space, and feel like it's already happened. When we are feeling good, everything flows more easily, and things just come to us in a way they can't when we are stuck looking at what's wrong. And mood has such an effect on immunity as well! Look up psychoneuroimmunology and the work of people like Bruce Lipton and Candace Pert if you don't already know.