3.2 Recommendations on Category Structure

It is recommended to keep your category path to 3 levels.  You can have more or less but 3 does a good job of allowing enough differentiation among the categories to allow good user experience on your cart.
Root Category 1 > Sub-Category 1 > Sub Sub-Category 1
Helmets > Street Helmets > Full Face Helmets
Helmets > Street Helmets > Open Face Helmets

This is typically how a category hierarchy would look, it is important to layout a good strategy for your categories before creating too many.  Often times you will find that you will need to make changes along the way so you want to plan as far ahead as possible.

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