Here's something that nobody mentionned and is kinda obvious. Fun. Make sure to have fun. Peronally I think its no use practicing 8 hours a day if you have to kick yourself to do it.
I prefer a good hour of fun then 3 hours of "I have to practice".
Sure, the more hours you put in the "better" you will be. But why are you playing music ? To be good and say look at me everyone I'm better then you or to enjoy this beautiful art and learn new things that helps you express yourself in a fun way? If its for the first option, well lock yourself up and practice practice practice because there's a lot of amazing technicians out there :).

Also, remember this, you dont have to be the best color mixer or the best brush manipulator in the world to make the most interesting paintings. Same goes for music. Have fun :)