The fastest way to get better at classical guitar is refining your overall tone. And this will always, always come from your fingers in an acoustic instrument such as this. In fact, finger tone tends to be a very personal thing in the classical guitar community: consider it as your version of an artist's signature whenever you play music out of your instrument. As long as you get your tone right, you will have something that will separate you from other guitarists out there. We've written a guide all about classical guitar technique here.