Learning is one of the essential pieces to growing yourself. No matter what level you're at, learning is a must. This doesn't mean going to school, or taking formal classes. Learning can come in all forms. One of the wonderful things about the modern age is that there are countless resources available on the Internet. You just need to know where to find them.
If you don't want to go hunting around for the resources you want there are some great courses on Lynda.com and Skillshare. These services provide structured video courses on almost anything you can imagine.
However, if you have the patience there are so many free resources out there to find. Try Googling for a tutorial on something you want to know and you'll more than likely find your answer. The main disadvantage is that you're not getting prepackaged lessons, and there is definitely more time involved in discovering helpful resources.
One of my favorite ways to learn however is examination. I love pouring over every detail of someone else's work, trying to figure out how it was put together. Even better, if the artist/designer has made any source files available then check those out. You will see exactly what techniques they used, making it easier to emulate.
However you choose to learn, never stop. Make it a point to learn something new all the time, and practice it. Get out of your comfort zone!