LiteSpeed provides you with an option to run the LiteSpeed webserver at the same time as Apache under an offset port so that you can test your new webserver without taking down your main one.
To perform this change you will need to log into your LiteSpeed admin portal.
Then navigate to:
Configuration >> Server >> General >> Using Apache Configuration File
Under the offset port choose an offset you would like, for example, if you choose 1000, then LiteSpeed will serve webpages under port 1080 & 1443.