I upgraded my laptop today, to Kubuntu 22.10. I could do it in place, but usually I use the opportunity of an operating system upgrade to also encourage me to have a good disaster recovery system, and I nuke the entire system. I usually don't actually test the DR set-up end-to-end, because that relies on downloading all my data again from my cloud backups, but deleting everything on my laptop every year or so does help keep me on top of my documentation. It also clears out all the cruft that accumulates and for which I no longer have any use. (Not that there aren't directories called 'unsorted' or 'keep-for-a-while' whose purpose I can't really remember!)
The usual way to do an upgrade like this is pretty simple. First, I bring a local USB HDD backup up to date (these drives are local ad hoc backups for me, and contain lots of stuff that I don't really need to back up). This is done with rsync, using something like the following command (note the trailing slashes on the directories… slash-or-not is probably the most annoying thing about rsync!):
rsync -a --delete-during \
The exclusion list is rubo77/rsync-homedir-excludes and is a useful way to not backup actually useless stuff like caches and trash.
The USB thumb drive that I usually use for installing Kubuntu was only 3.7GB, which for previous versions has been fine. However, 22.10 seems to be larger, and the .iso is 4GB, so I had to use a different thumb drive (and 8GB one). I'll have to find a new penguin sticker. Copying the .iso to the drive is done with
usb-creator-kde (a.k.a. Startup Disk Creator), with which you select the source .iso and the destination disk, and that's about it.