The three-stone principle
Almost every experienced sharpener settles on a three-stone progression: a coarse stone (400–1000 grit) for primary work and geometry repair, a medium stone (2000–4000 grit) for refining the scratch pattern, and a finishing stone (8000–16000 grit) for the final edge. This system is simple, efficient, and covers 99% of tool maintenance situations. Resist the temptation to buy 10 stones before you've learned 3.
Splash-and-go vs soaking stones
Soaking stones (typically magnesia-bonded, like King) must sit in water for 10–15 minutes before use. This is inconvenient for quick daily maintenance. Splash-and-go stones (typically vitrified, like Shapton Glass) need only a few drops of water applied immediately before use. For professional or frequent use, splash-and-go stones are far more practical. For occasional use, soaking stones' lower cost may justify the inconvenience.
Flattening is not optional
A concave stone cannot sharpen a flat blade. Every stone must be regularly flattened on a diamond lapping plate or a dedicated flattening stone. The Atoma 140 or 400 diamond plate is the universal recommendation for this task. Budget for one before you buy your first waterstone — learning to check and correct stone flatness is the foundation every other sharpening skill is built on.
Recommended starter kit
Atoma 400 diamond plate (for flattening) + Shapton Glass 1000 (primary) + Naniwa Chosera 3000 (intermediate) + Shapton Glass 8000 (finishing) + Leather strop. This five-item kit costs approximately $300–$350 and will last a lifetime with proper care. Every stone can be used on every Japanese tool. This is the system used by the majority of serious Western Japanese tool enthusiasts.
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