Its very simple actually.
The main thing to do is ditch specifying a folder whenever you reference an asset. Any that dont exist in the same folder you are running the process in can be linked so they appear in the same folder or you can specify the folder path but ensure that folder is consistently named etc in Dev>Test>Prod tenants.
After that you should have an easy time, when you add a process to a folder the second page in the wizard will list all the assets you use and if they are present or not, its a nice validation to check that an asset wasn’t missed and lets you configure them immediately and there are buttons to add missing assets on that page making it fast an efficient.
Alternatively solutions such as ‘Solutions Management’ can help you build a package of your process(es) assets, queues, storage buckets etc that you require to make it easily portable between tenants.