If [hats in chicago] clicks are converting into sales you should be careful about playing with this in case you lose the ranking altogether. Saying that, individual product pages usually convert better than anything else so it may be best to concentrate on those instead of category pages. To rank a category page that lists the hats you have available there are a number of things you can do if you haven't already:
- If you don't want the homepage to rank, make sure you're not committing keyword cannibilisation
- Ensure your onpage SEO is spot-on for the hat page e.g. title tag with your keyword (and maybe a price/offer/incentive to encourage clicks, meta description to encourage clicks, descriptive image filenames and alt attributes, useful URL structure
- Onpage too - add some unique introductory text
- Show review data (such as AggregateRating) by each product and consider adding a small number of reviews to category pages - user generated content is good for getting unique content. I say a small number of reviews to avoid duplicate content issues
- Link to your most important category pages from every page on your website via a main menu
- Add breadcrumbs
- Make sure you have an HTML sitemap, and an XML sitemap submitted to the search engines - both listen all your pages