The short answer to this question is a resounding: “You can’t!” Although a common myth is that our noses and ears continue to grow as we age, the reality is that bone cells (osteocytes), as well as cartilaginous cells (chondrocytes), develop oxidative stress as we age – which means they degenerate, not continue to grow. The real reason our noses and ears look larger: gravity. This leads to drooping and the illusion that these appendages get bigger with time.
There is only one scenario in which your nose could get smaller naturally, and that is if you lose massive amounts of weight. Believe it or not, there is a layer of fat that is just under the skin of the nose.
If a smaller nose is what you desire, I recommend meeting with a Board-Certified plastic surgeon experienced in rhinoplasty who will accurately examine your nose, create a 3D simulation showing your what your nose could look like after surgery, and develop a plan tailored to your individual needs and wishes. Good luck!