I'm in the middle of cleaning up my clients Tealium account. I've followed these steps:
What's left are the extensions. How to check if they are still used? I think I have to manually check each one of them to see if it's still in use?
That way I can log this and see the unused ones. A bit like the "Tag Reporting" dashboard in the "My IQ" tab, but more specified for each tag/loadrule/udo.