How do I perform A/B website testing?
If I change the CSS, as soon as I reload the page (in the Network tab) it reloads the original CSS - obviously.
You need to perform your A/B testing in a different way.
Below are some recommendations.
The Ultimate Guide To A/B Testing
Create Your First A/B Test
Once you’ve decided what to test, the next step, of course, is to
select a tool for the job. If you want a free basic tool and don’t
If you want an easier alternative with extra features, go with Visual
Website Optimizer (disclaimer: my start-up).
Other options are available, which I discuss at the end of this post.
Setting up the core test is more or less similar for all tools, so we
can discuss it while remaining tool-agnostic.
You can set up an A/B test in one of two ways:
Replace the element to be tested before the page loads
If you are testing a single element on a Web page—say, the sign-up button—then you’ll need to create variations of that button (in HTML)
in your testing tool.
When the test is live, the A/B tool will randomly replace the original button on the page with one of the variations before
displaying the page to the visitor.
Redirect to another page
If you want to A/B test an entire page—say, a green theme vs. a red theme—then you’ll need to create and upload a new page on your
For example, if your home page is http://www.example.com/index.html, then you’ll need to create a
variation located at http://www.example.com/index1.html. When the test
runs, your tool will redirect some visitors to one of your alternate
Source The Ultimate Guide To A/B Testing