If you don’t study with a private teacher, then it’s up to you to evaluate your own skills. Record yourself whenever you can, date the recording, and save it. I learn the most from video taping my gigs. Seeing myself play live really helps diagnose the weaker points in my guitar playing and musicianship. I find recording to be the best method of self assessment available, and listening to recordings made over a year ago really helps me chart improvements.Although I sometimes need to force my eyes open to watch whenever my playing is recorded on video, there is no better or more honest way to gauge the level of your playing. [Also useful and no less painful: videotape yourself teaching!]
Cameron's sections on goal-setting, prioritizing, and time management are a must-read. It can be harder to schedule practicing when you're a pro, and since you no longer hear the motivational talk from a teacher to get you fired up every week, you'll have to create that impetus yourself.
Previously on the Collaborative Piano Blog:
31 Days to Better Practicing: The Complete Series
15 Ways To Add 10-minute Practice Blocks To Your Routine
Organize Your Practice Time Like a Stage Director
Degree Programs in Piano Pedagogy