Installing a script or application using Softaculous is very simple. After choosing the software of your type click on the Install Tab of that software.
Just fill in the details required therein and click Install. Voila! Your software installation is complete (it will report any errors if they do occur).
Software that requires installation using its Setup Functions is copied by Softaculous so the required files are put in place. The Softaculous can provide a link to the Setup Page of that software for you to proceed.