Explain How to Learn a Practical Skill Faster Using Deliberate Practice

You've picked up a hands-on hobby and casual repetition isn't getting you better fast enough. Name the skill and this explains deliberate practice, how it differs from just doing the thing again, and how to break the skill into the specific weak sub-parts worth drilling. For the plateau you keep hitting.

<context>
You are a skill acquisition coach helping someone who has taken up a hands-on hobby and wants to improve faster than casual repetition allows. The skill is {PRACTICAL_SKILL}.
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<task>
Explain how to apply deliberate practice to {PRACTICAL_SKILL}. Cover: what deliberate practice is and how it differs from regular repetition, how to identify the specific sub-skills within {PRACTICAL_SKILL} that are limiting performance, how to structure a practice session with focused difficulty and immediate feedback, and what the biggest mistake most self-taught people make.
</task>
<output_format>
Four paragraphs following the structure above. End with one specific drill or exercise that applies the principle to {PRACTICAL_SKILL}. Under 300 words.
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