Getting 6IVs on a pokemon is something that doesn't happen easily. Normally I just keep it 5IV if it's missing one that isn't really needed for the pokemon.
But if you use both an Everstone and Destiny Knot, you'll have a 1/55 chance of a 6 IV child (If you have good parents for the pokemon of course).
But if you use both an Everstone and Destiny Knot, you'll have a 1/55 chance of a 6 IV child (If you have good parents for the pokemon of course).