Roll 6d20 and keep the results in order and build your character around that. Here are some examples.
17+1 Str, 17+1 Dex, 16 Con, 1 Int, 8 Wis, 20 Cha
I'm a naked vhuman Frenzy Barbarian with the tavern brawler feat at level 1. I'm not smart enough to use a weapon or be any other class than barbarian. I probably sleep on the floor or even outside, but man am I good looking and liked by all. Basically a human puppy dog lol
6 Str, 16 Dex, 17+1 Con, 6 Int, 7+1 Wis, 20+2 Cha
Bella, the Half-Elf Bard, is possibly the most beautiful creature the world has ever seen, but she's dumber than a box of nails.
10+2 Str, 20 Dex, 12 Con, 14 Int, 4 Wis, 5+1 Cha
He's a Dragonborn with no name that was raised in captivity by a Red Dragon. He eventually escapes using his stealth and self taught ability to pick a lock. Never experiencing contact from the outside world, he is smart, but ignorant, and does not know how to speak. I imagine he would be pretty disgusting but also really gullible.
Oh yeah he would be a Rogue Thief.
Anyway, the roll 6d20 method is pretty fun.