Over at eCommerce Optimization a well thought-through and very thorough list was posted called eCommerce & Shopping Cart Usability: 21 Best Practices. In this great article, the author ‘eCopt’ lists 20 very solid recommendations for any ecommerce site. The 21st on the other hand, is an absolute show stopper:

Test different combinations of best practices to see which ones produce the best results for your store and shopping cart.

It always amazes me how people take a “best practice” and immediately implement it on their website. Oh, you don’t have shiny blue Ajax effect #12? Well, what are you waiting for!? It worked for those guys, of course it will work for us.

The fact of the matter is that websites are different - Gasp! But what people don’t seem to realize is that you could design your website features to be identical to your main competitor, but still get different results out of them. Why?

You have different visitors. The people who visit your site are not the same as the people who visit any other site. There will almost definitely be a large overlap with your competition, but the differences that make your visitors unique are important. They might not respond to the same features in the same way.

Going back to the article -  eCopt lists 20 best practices, such as “Keep the site search function above the fold and in plain view so shoppers can query the catalog anytime” and “Show related products and cross sell before the checkout process and after items have been added to the cart.” These two and the 18 more are all great general guidelines for success to consider with your site. Some of them will work for you and some of them won’t. The important thing is number 21, mentioned above.

When you are considering implementing an added feature, the best thing to determine first is how you are going to measure it. Anything you do on your site that you are not measuring is likely a waste of time, simply because most people will find that there are a lot more ideas that won’t work than ones that will. One of the smartest things you can do is design and code with measurement and testing in mind.

So decide how to measure your new feature. It could be as simple as an increase in conversion or a decrease in bounce rate. When you code up your newfangled thing, make sure that you can A/B test it against the previous version - and really test it. Make sure you are getting significant results, and look at all your metrics to make sure there are not unexpected surprises. Then roll it out full board.