I believe that a person's physical body and conscious mind are two strong forces that determine the nature of reality. Manifestation can develop based upon how a person perceives the nature of reality. A person can set limitations and restrictions on the nature of reality depending on their scope of it. If the person has the right mind set, passion, desire, or truly believes in something, then manifestation can occur. However on the other end of the spectrum of reality there is a restriction; for example, natural laws of gravity. .
A person must be very clear on what they want in order to manifest it. If they want success in life they have to reach for it and set goals. They use their conscious mind to yearn for the success and the results that come with it. If an athlete uses their body to manifest themselves into a supreme athlete then that is the reality that comes forth. .
The conscious mind is very powerful and can manifest our own diseases. The thought of beasts or ghosts will reaffirm fear and cause insomnia. Thoughts that are held in or speculated can come back to haunt us. Causing emotional problems that can lead to health complications. .
Although manifesting a reality is possible by your own force of mind and body, there are restrictions that limit you as well. Time and distance is a factor that you cannot manipulate. You cannot hope for the time to pass and to be somewhere in an instant; you must wait. The space around you is a set constant; you can move furniture around but the space around you is still what it was before.
My point would be that you can manifest anything that the natural set law does not restrict you to. Some of the restrictions are time, distance, space, mathematical equation and formulas, and the cycle of life.