Once you have your main product categories, what next? Ordering them can be a little tricky.
When someone visits an online store, in most cases they’re seeking something specific. Since there is no way to tailor your website uniquely for every new visitor (this can hopefully be accomplished in the future), the most effective method is displaying your most popular categories first. Odds are they’ll see what they want more quickly and make a purchase. The longer a customer spends scrolling without seeing what they came for the more likely they are to bounce.
Other Ordering Options
Other configurations aren’t nearly as effective. A random ordering is just plain silly and is unlikely to yield the best results. You’d basically be tossing a coin and hoping you get lucky.
An alphabetic arrangement is the simplest but it can be counterintuitive especially if you have many product categories. Which you shouldn’t have by the way. Keep the number of your main categories between five and seven. If you must have more categories, try not to display them all at once. Too many options have been found to induce choice paralysis which will cost you conversions.
Displaying your categories horizontally is recommended on desktop. A vertical arrangement is acceptable on mobile (in the burger menu) due to limited screen real estate. See the best practice about adding a link bar.
3 Levels of Sub-Categories
It’s also wise to limit the sub-categories of each category to about three levels. Any more would needlessly complicate navigation, annoy your users who may be unable to find what they want, and ultimately lower your conversions.
As an example, from what I could find, Adidas sells more to men than women, and so a fair assumption is that their menu items are ordered by sales volume.