Erm, I wouldn't say I'm good at all, but I approach learning anything, especially art, in three basic ways:
- Do it.
- Do it mindfully.
- Accept and acknowledge crap, and move on.
Do it: You just have to sit on your ass and DO the thing you're trying to get better at. Reading 10,000 blog posts on composing isn't going to make you better; you have to compose. As a writer, I've written 5 novels in the last 2.5 years, and now I can say they're worth reading.
Do it mindfully: I used to tell my students that "Practice doesn't make perfect. Practice makes habits. PERFECT practice makes perfect." If you're "doing it" above but you're not being mindful about ways you can get better, you're going to stay stagnant or, worse, create bad habits. If I practice my piano scales at blinding speed with errors, I get really, really good at playing them really, really poorly. This is the part where I'm also reading, learning, asking questions of experts, and then trying to apply it to what I'm working on.
Accept crap: I have lots of unfinished projects, both in writing and in music, that are crap. But each one of those turds came with a golden nugget of learning (or corn, I never could figure that out). Those hunks of steaming poop don't define you as an artist, and you have to let them go and acknowledge that they taught you something that you can then apply to #1 and #2 (no pun intended)
The real lesson is you gotta put in the time. If you're interested in this kind of stuff, Malcom Gladwell wrote a book called Outliers where he explores "geniuses" and how in many cases it just becomes an opportunity for a person to put in monumental amounts of time into one activity.