For certain you're going to upgrade EEM and Process Automation first, I'd say in that order.
As far as Service Desk, Service Catalog and USS is concerned, the order shouldn't matter too much. You can technically run the installer and upgrade all at once, but if you'd rather do one at a time I'd say start with either Service Desk or Service Catalog, and do USS last.
Looks like you have EEM, ITPAM, Service Desk Manager, Service Catalog and USS installed.
What version(s) of each software is installed?
Do you have other server(s) in the environment or is everything installed on a single server?
Do you have any additional questions on this topic based on the information that Alex provided?
If not, please mark Alex's question as correct so this thread can be closed.
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