Here are a few links regarding rolling dice to derive wordlists. Keep in mind that even if you use the 2048 word BIP39 list, it may not work as a wallet passphrase because the checksum feature that is built into the BIP39 wordlist derivation function is not being used for "rolling your own". There is a utility on github called "force39" that will tweak a hand-rolled wordlist to be compliant with what BIP39 wallets will expect.