Bip39 Checksum. Entropy values must be sourced from a powerful supply of randomness. This suggests flipping a fair coin, rolling a good dice, sounds measurements etc. Will not use phrases from guides, lyrics from tunes, your birthday or steet tackle, keyboard mashing, or anything at all you think is random, https://ezylinkdirectory.com/listings13068104/bip39-seed-phrase-https-linktr-ee-bip39-bip39-word-list-pdf-options