First you'd use 10 Protein, 10 HP ups and 10 Carbos then assuming that you do have the Power items you'd fight 15 Lillipups/Patrats/Mienfoo/Golett (1 Atk EV) with the Power Bracer on and then fight one more of them with it off (alternatively you could use the appropriate wing to get those last 2 Atk EV points)Alright so imma EV train my pokemon. It has pokerus . I want to EV train it 252 in attack and 126 in hp and 126 in speed. How much and which kind of pokemon should I kill for it to gain this? Do i still give it the medicines?
Then for HP you'd either run around for Audinos or Stunfisk (2 HP EVs) and fight 2 Audino/Stunfisk with the Power Weight on and then one more without it.
Finally for Speed you'd Surf for Basculin and fight 2 with the Power Anklet on and then one with it off
That should finish off with 252 Atk, 128 HP and Speed.