It's too easy just login into your FTP account or file manager for cPanel users
and add this code to your site's .htaccess file
rewrite rules Example:
Cache all URLs for 2 mins excluding ''/administrator'' URLs
########## Begin - Litespeed cache
<IfModule LiteSpeed>
RewriteEngine On
CacheDisable public /
RewriteCond %{REQUEST_METHOD} ^HEAD|GET$
RewriteCond %{ORG_REQ_URI} !/administrator
RewriteRule .* - [E=Cache-Control:max-age=120]
</IfModule>
########## End - Litespeed cache
and save it
to verify Litespeed cache is working or no
simple
visit
http://www.webconfs.com/http-header-check.php