You could always have it memorized.
This is really the worst idea in my opinion, who can remember more than 20 words containing uppercase and lowercase characters, it's not an easy thing to do especially for a long time.
You could also go on your mobile, to the notes app probably already installed on your device and have it written and stored there. Then safeguard it all with a password or whatever security lock your device uses.
How sure are you that the recovery phrase will be safe there. I don't recommend saving the backup recovery phrase in the above way, it's too risky for me. You should consider choosing the media or place as you mentioned because it is very vulnerable to the risk of being lost or damaged.
If you don't want to have the same fate as this user, then consider storing the recovery phrase in a safer place.
This wallet I created in 2017. Then Im sure I copied the private keys but I think its saved in a hard drive that is broken.