How often do you change the displays in your front windows? Depending on your jewelers block insurance you might well be emptying those window displays every night; which give you a chance for creativity every morning when you set them up again.
We have to assume you change the whole display at least once a month. How do you determine what to put out there? Do you think about the current season? The current holiday? Town Events? Do you match your current advertising? Each of these ideas touches on some form of merchandising.
Updates to your website should be considered the same as updates to your front windows. You only have a few seconds to attract someone's attention as they walk by your front window, and it's the same for your website. Something out on the internet brought the customer to your home page, and you only have a few seconds to attract their attention before they click back and disappear forever.
If we extend this idea of merchandising online, you need to think about every potential landing page that Google might send traffic to. Normally, because of your website design, the landing pages will be very obvious to Google. Assuming you have your website split into subsections of pages, each main section page will serve as a landing page, and therefore each of these pages needs to be viewed as if it were a storefront window.
Merchandising each of your landing pages will take a bit of thought. If you have a large website it might even take 4 weeks to update them all one at a time, only to go back and do it all over again. You might want to change the largest photo on every landing page every month. After all, your jewelry store has a lot of beautiful items in it, why not take turns showing them all off.
In fact, one strategy might be to show jewelry featuring the birthstone of the month. I.e. on the Earrings landing page you could show peal earrings (since it's June) and on the Rings landing page you could show settings with alexandrite gemstones (again, since it's June).
The landing pages people visit today will not be the same pages they visit tomorrow. If you get them to make a purchase, it won't be because they bought the first item that got their attention, but something they feel comfortable buying after browsing around your site.
Relate the online buying experience to how someone shops in your store. When someone is in your brick & mortar store and is "just browsing" or "just looking" they may not have an agenda, but if they see something nice they will make a purchase. Believe it or not, the same happens online.
So as someone browses around your website, you should give them something interesting to look at, rather than just the same old stuff month after month.
Updates throughout your website are just as important as updates to your home page. Next time you change your window displays around, think about how those same changes could be made online.