How I wish that I could tell you how to be a great musician in a blog post, or in a lesson. The very most that I can do is to inspire you to be sensitive to the meaning of what the composer has written on the page, and how to interpret black squiggles, slashes, and dots into music: artful sound.
What I can tell you is to listen. Listen carefully to everything around you, and most of all, listen voraciously to the great musicians of the past and present. In this age of the internet, so much is available at your fingertips, but even so, nothing is as exciting as a live performance.
The most important thing to do, of course, is to practice, but to never practice without listening. As soon as you start practicing without listening to what you are doing, your work starts to become a waste of time.