Installing Unless is very simple and it will work on any website, any CMS, and any page builder. It does not matter which back-end system you are running, because Unless operates in the web browser only.
The install procedure works similar to many other client-side services, by adding a single line of script to your website. After you created an Unless account, you can add the Unless snippet.
Adding the snippet
In your Unless account, you will be presented with a script snippet that will need to be applied to your website. You should add this snippet to the top of the HTML head section of each of your web pages. If you don’t know what that means, it is best to use an installer instead, as explained in the next section.
So, make sure that the Unless snippet is available in all the web pages that you are planning to personalize, but also on all pages that you might use to classify your visitors - like landing pages or search pages. However, the simplest way to avoid such problems is to add the snippet on all website pages.
By the way, you can’t use a tag manager (like GTM - Google Tag Manager) to install the Unless snippet. The reason is that tag managers tend to load all their scripts after the host web page has loaded fully. This means that the original content of the web page will already be visible before we can personalize it. This leads to a flash of content, which is generally considered a very bad user experience and a conversion killer.