If you run a page of your site through a page speed tool, it is likely that at or near the top of the suggestion list are things like reduce unused JavaScript and CSS or 'Eliminate Render-blocking Resources'.
This critical factor typically means take a look at the CSS and especially JavaScript resources added to the page. First though, such coding is part and parcel of how web content is created. Web page styling and functionality would not be the same without them. Especially dynamic and interactive content. However, bear in mind that each CSS and JavaScript request has to be processed by your users' browsers or the server before a page will load fully. When a browser normally finds CSS or JavaScript <script> tags, it will stop loading HTML until the scripts have been parsed, compiled and executed. And having to do this multiple times slows down the overall page render time.
And even even if the JavaScript is not render-blocking, it competes for bandwidth with other resources while it's downloading, which has significant performance implications. Sending unused code over the network is also wasteful for mobile users who don't have unlimited data plans.
So one of the most beneficial things you can do is to ensure your styles and (especially) scripts follow page load efficiency practices and utilise the tools the Customer Self Service eCommerce Platform has to help achieve this.
Think about the content especially images (and other rich media) on your pages, especially on key pages such as the home page and SEO landing pages. As a guide, keep an image’s dimensions (h x w in px) to only as large as is needed to fill its container. And experiment with compression to reduce file size (kb) while making sure visual experience is not compromised. TIP - The home page as well as product pages should be priority since it is usually the first page for users and SEO search results. Find out what other pages are common SEO landing pages on your site. Here is an article with useful tips.
Also consider the implications of campaigns, and the number of products in them. TIP - Limit to one campaign with a maximum of 5 products for desktop and 2 for mobile.
Ensure Lazy Loading is enabled. The Lazy Loading feature ensures that the loading of non-critical files are delayed until they are scrolled into view (on screen or what is called 'above the fold').
Here's an example of how lazy loading works. Suppose your home page has a slider campaign. Only one slide is viewable on your user's screen. With lazy loading enabled, an image file will not be loaded until the slide is in view. This allows non-critical files to be delayed until needed.
If your site uses third party plugins and addons such as marketing and tracking software and scripts, test that they are not adversely affecting page load speeds.
There's quite a bit your eCommerce team can do to help increase page load speeds. Keep monitoring, testing and optimising! If you require further assistance than this, book a Professional Services consultation to assess your site and implement additional measures.