Quick EXP
Fly to the resort area once the NAtional pokedex has been unlocked. Then give the desired pokemon the EXP. Share. Battle with high pokemon as the pokemon are lvl 50+. You can get some rare pokemon like Oddish, Gloom, Pinsir and if you head north yoou can encounter Beldum and Cacturne etc. Good luck. I use this all the time to raise my eggs and evolve the
pokemon!