Thanks for all the replies / help.
No, it's not about having a lot of BTC. Actually it's only to make a paper wallet for a non computer savvy friend who wants to buy a small amount to start and I want to put it in a paper wallet for extra security for him.
I will follow the advice about printing some garbage and clearing the spooler, but I thought that some modern printers actually had a sort of hard disk inside that stores many images of scans or prints, even if you clear the PC printing spooler ?
Of course, always using Linux for anything related to btc.
No time to purchase the HW wallet as he wants to buy soon. Will get one for myself though, thanks.