When I want to improve at something quickly, I find a tutor who is slightly better than me.
Why only slightly better?
In my experience, it's frustrating to learn from a tutor who is much better than me. They've often forgotten what it feels like to be a beginner, which is a worse experience for both of us. I'm confused; they're bored. Not a good combo.
Finding someone slightly better has a few nice properties. Their skill level seems achievable, so I'm motivated to work hard. They give better advice since they remember what it's like to be in my position. And they generally cost less and have more free time.
Improvement comes from struggling and eventually succeeding. A good tutor pushes me outside of my comfort zone while motivating me to keep coming back.