If you’re not familiar with Next Experience Banner Annoucements, I highly suggest checking out the docs.
Basically, it’s an easy way to display a banner for logged in users.
I like to use this for our subprod environments, so users/admins/developers can easily distinguish between dev and prod.
To configure these annoucenments automatically after a clone

simply add this to, or create a new clone cleanup script.
createUXBanner();
function createUXBanner() {
var instanceName = gs.getProperty('instance_name');
var time = new GlideDateTime().getDisplayValue();
var uxBanner = new GlideRecord('sys_ux_banner_announcement');
uxBanner.initialize();
uxBanner.heading = instanceName + " environment. | Last cloned: " + time;
uxBanner.start = time;
uxBanner.non_dismissible = true;
uxBanner.color = 'warning';
var banner = uxBanner.insert();
var uniNav = new GlideRecord('sys_ux_m2m_banner_announcement');
uniNav.initialize();
uniNav.announcement = banner;
uniNav.announcement_config = '36aefd8153223010f296ddeeff7b12e9'; // set to 'Unified Navigation'
uniNav.insert();
}
