The most effective factor to do is use a safe passphrase along with your 12/24 phrase phrase, and maintain the passphrase in a separate location, and even no location in any respect however your head and possibly share it with a number of relations.
Utilizing BIP-39, the identical 24-words with a special passphrase will create fully disjoint wallets which can’t be linked by exterior remark. You possibly can maintain reusing the identical phrases and have totally different wallets through the use of totally different passphrases. Be sure passphrases are an inexpensive size and complexity and never dictionary phrases or birthdays. Nonetheless, brute-forcing these is tough as a result of PBKDF2 is used for hashing, so that you needn’t go overboard and use a passphrase you may overlook.
It could be a good suggestion to incorporate a small quantity of bitcoin within the pockets utilizing your 24 phrases, however with no passphrase. This could function a ‘decoy’ pockets, which may be monitored for exercise to find in case your 24-words have been compromised. It additionally serves to permit believable deniability to the quantity of bitcoin you personal, as a result of if you’re beneath duress from an individual (the State for instance) attempting to power the knowledge out of you, they can’t presumably know what number of wallets are created from the identical 24 phrases. You possibly can plausibly declare that what’s within the decoy pockets is all of the bitcoin you personal.
Since each the 24-word phrase and your passphrase are essential to entry your funds, the safety of the 24-word phrase isn’t as paramount as with out the passphrase. You need to make a copy on a metal plate to withstand pure disasters, and maintain a written paper copy in one other location which is extra accessible to you, however which may be safely disposed of with hearth.