The software and experience is quite user friendly but you'll need to make sure you understand what you're doing lest you make a mistake.

First, you'll need to generate a few private keys offline. You can use the SeedSigner (same hardware) to do this if you want or hardware wallets. Then you must create a wallet descriptor using these private keys. It is imperative that while doing this you don't expose your private keys on an internet connected computer.

Then, on the SeedHammer controller, you need to enter each private key and scan the wallet descriptor. Be sure to check that the descriptor contains the same private keys you generated in case the computer you used to generate the descriptor is compromised. Then all you need to do is follow the instructions on the screen of the controller which is periodically changing plates. Each plate engraving takes a maximum of 20 minutes. The engraving is very loud though so you should do this in a place where you won't disturb people. I had to stop because my apartment neighbors complained.

The device itself has no memory or storage (it's intentionally chosen because it's dumb) so you can loan it to whomever you want. If you're more paranoid you can use a new controller (Raspberry Pi) if you're borrowing someone's but as long as you personally prepare the SD card (and verify the software) then you'll be fine.