Bip39. Entropy values needs to be sourced from a powerful source of randomness. This means flipping a fair coin, rolling a fair dice, sound measurements and so forth. Never use phrases from guides, lyrics from tunes, your birthday or steet tackle, keyboard mashing, or something you think is random, mainly https://iseodirectory.com/listings13058623/bip39-mnemonic-https-linktr-ee-bip39-a-secret-weapon-for-bip39-mnemonic-generator