Practice and do your best. Focus and express yourself. You can take classes, study in books yourself anything basically. Don't give it up if you got it, if you don't have it keep pushing yourself to try. Listen to music that meditates your mind and let your imagination take control. You'll be amazed with what you've done.
Practicing, also make sure you know what medium you are best with. I had this same question about a year ago, I recommend you watch some of the bob Ross tutorials. He's a weird guy but his methods work really well. Once you learn other peoples techniques it makes it easier to make your own. :) good luck!