Your conscious mind is only aware of 1 billionth of what is around you. And what your non conscious mind makes your conscious mind aware of is based on your beliefs, your past experiences in life, what you expect to happen in the future, what you want to happen in the future, all rolled into one.
So when you create your reality you are not so much “making” stuff manifest out of thin air, as much as you are reprogramming your non conscious mind to bring new things to your conscious awareness.
And with new experiences and things brought to your conscious awareness, your reality will literally be different. You will literally create your reality as you want. Rather than as your past programming, beliefs and ideas have dictated.
There a couple ways to change beliefs. Go here to read about them