A local diceware generator is probably available in your package manager, e.g:
sudo apt install diceware
diceware -n 6
QuickenPrisonThermosDefilingBasicsVengefulA local diceware generator is probably available in your package manager, e.g:
sudo apt install diceware
diceware -n 6
QuickenPrisonThermosDefilingBasicsVengefulFor all of its faults, 5x six-sided dice looking up this wordlist (https://theworld.com/~reinhold/diceware.wordlist.asc) is something that can be accomplished by hand, without computer assistance.
Assuming you have trustworthy dice (they don't have to be perfectly balanced, just something you can trust to be random), then you can diceware your own password by hand.
I'm just a humble non-crytographic-programmer making practical suggestions with the most substantial security improvement for the least effort... Of course personally - I roll dice, dice that I whittled out of sticks, sticks from different trees that I collected from different parks, parks that I visited in a random order based on the results of a PRNG of my own secret design, a PRNG I built out of swarm crab based logic gates on a secret beach, seeded with a number collected from a geiger counter and small sample of u238, a geiger counter I constructed from photodiodes and aluminium foil, photodiodes I fabricated out of mud, rocks and fire. One day I hope to finish implementing my own general purpose computer and browser, then I will finally be able to use my passwords :)
For example, randomly selecting words from the Basic English Wordlist (https://simple.wikipedia.org/wiki/Wikipedia:Basic_English_co...), a list of 2626 words, could be a better methodology.
https://www.eff.org/deeplinks/2016/07/new-wordlists-random-p...
cat /usr/share/dict/words | shuf | head -n 4pwgen with the -s option will generate 'random' passwords, up to the randomness limit of whatever random source is provided by your kernel and system.