You could make your own sort of "encryption algorithm" just so if ever someone gets a glimpse over your seed, they wouldn't be able to steal your coins. Like, probably instead of writing your seed straight on, probably take a look at the word list and list the words above or under your seed words instead. This example is definitely not a good way to do it, but I hope you get the idea.
That's exactly what I thought of first but considering I don't know of a good way to do that, it'd probably very easy for them to find out. Which is why I think I'll end up with something more visual like the pattern key I use on my phone.
Since other posters already suggested good ideas, I'd like to share one sort of "unorthodox" way of storing your mnemonic phrases.
Memorize it. Yes, you heard that right. A 12-word recovery seed is a lot easier to memorize that most people thought(though memorizing 24-word seed is still possible, just significantly harder). But I understand that this is definitely not for everyone.
As someone who routinely forget passwords for sites and ending up having to have a reset request sent, this is definitely not for me.
they also set up a completely different 12th(24th) word(as a surrogate) with just a few satoshi's on that seed phrase incase ever physically aproached by someone with a hammer or gun demanding the whole 12(24) words... you simply give the 11(23) normal words. plus the surrogate 12th(24th) word to get them to leave you alone saying its all you have... knowing it would only cost you a few lost sats to be left alone
OK I'm noob when it comes to the tech side and I've only used Electrum and just go with standard setting and the seed it generates. Are you referring to the optional seed extension or are you talking about making a dummy wallet using the same seed as the main wallet save for the last word so that it would be easy for to memorize?