>>14686745>First and foremost you need to have a ditto (or breeding partner) with 3 max IVs, which is incredibly, INCREDIBLY rare.You only need one ditto for each of the six stats. Catching all the dittos is time consuming but only needs to be done once, and dittos with 2x 31 IVs aren't too uncommon (especially if you can find someone whose Friend Safari gives Dittos).
1: Ditto with desired IV with Power item + the pokemon you want a well-bred version of.
Breed until you get the nature you want (1 out of 25 eggs). Males can pass on Natures with Everstone now, and it's 100% of all eggs retain the nature.
2: Ditto with another desired IV with Power item + the pokemon with the right nature [it will also have a 31 IV from the previous Ditto].
Breed until you get a Pokemon that has inherited the IV from the non-Ditto. This is 1/25 eggs, iirc.
3: Ditto with the third desired IV with Power item + the one you just got, which has two 31 IVs and the right nature.
Breed until you get a Pokemon that has inherited the two IVs from the non-Ditto. This is 1/50 eggs.
This is even faster if you have a ditto with two maxed IVs.
>>14686851Replace step three by breeding the Pokemon that knows the egg move with a Ditto with an IV. It will have the eggs moves, and a 31 IV.