You learn a new song and there is this place that gives you so much more trouble than all the rest. First thing that usually comes to our minds is: “practise the hell out of this bugger!”. But now is not the time for mindless repetition. Actually it’s probably the most inefficient thing you could do. Instead it’s time for some mental work. Here are some guidelines:
- Isolate the difficult part. Find last easy (comparatively) notes and where the difficult part ends.
- Is the difficulty of the part in technique? Or maybe you don’t understand the rhythm?
- Is the problem in your right hand, left hand? Maybe both hands are difficult or rather it’s not a problem of each hand separately or synchronization between two hands?
- Can you play it correctly very slow? If you can, notice what happens when you speed up? What is the core of your problem? Tension, slow movement, precision, stretch?
- Once you have the problem pinned down you might be ready to go rest of the road with brute force approach. But if you have any doubts keep going to the next point.
- Try isolating just the troublesome movement. The more you narrow it down the easier it’ll be.
- Cut out all that is irrelevant for your problem. If problem is just in one hand, cut the other. Divide the movement into segments (for example if it’s arpeggio practise just two-three fingers at a time. If it’s a chord change, learn just the vertical movement and then horizontal separately).
- If you see that difficulty would be much better addressed in some kind of technical exercise that you know or can come up with, go for it.
- Once you know the fundamental part, “dress it up” progressively with more and more of what you cut before until you’re back where you started.
With time and experience you’ll be able to skip steps and arrive at conclusions almost intuitively. For that to develop, however: you’ll have to do those steps consciously for some time.