In a 'Practice makes a man perfect' story, the first important element is the initial struggle. The character has to face difficulties in the beginning, like a novice cook who burns every dish at first. Then comes the consistency of practice. They can't just practice once in a while. It has to be a regular thing. For instance, a guitarist who practices for a set amount of time each day. And finally, there should be a visible outcome of the practice. The person should achieve a certain level of proficiency, whether it's a carpenter making perfect furniture or a singer hitting all the right notes after much practice.