You could split the seed up and hide in multiple spots. Even if one is stumbled upon they would still need the other pieces. You would only need to remember the order.
Discussion
Probably the safest method. + you can encrypt the words in other letters, numbers or symbols so if someone see it he can't remember easily the words because they looks like random letters
Even one wrong letter, one or two words missing could add an extra layer of protection.
Changing to a new wallet/key when in a better situation would be good too. Also of course a passphrase.
Border wallets (probably best for a temporary wallet and or if needed in a transportation pinch). Paper wallets. You can code your key in a similar way that Benjamin Franklin used code etc. Blockstream has a cool cryptography book that can help.
As btc sessions, not over complicating things for yourself I think is wise too.
Never. Split. Up. The. Mnemonic.
Passphrase or multisig instead.