Here's a little rundown with how Masuda Method works, for those of you who breed for shinies.
Basically, you'll want a Pokemon from a region different from where your copy of the game was purchased, and a Pokemon native to your region. Place them in the Day Care on Route 7. Make sure, if you want to hatch eggs quickly, that you have a Pokemon with the Ability Flame Body or Magma Armor, which helps with Egg Cycles.
You can take a penny or a dime and place it under the circle pad on your 3DS to go in one direction in Centrico Plaza, which has a set circle with little/no obstacles. Easy hatching, but you have to switch your hatched Pokemon with every batch of five.
Few tips:
-Every time the Masuda Method is used, the game will make extra attempts to spawn a shiny.
-Each egg has the same probability of being shiny.
-The Pokemon has to have a specific PID (Pokemon ID) that will decide if it's shiny or not when XOR'd with your Secret ID (Unviewable) and your Trainer ID after they're converted into binary. If the resulting number is less than 16 (previously < 8 ) you have a shiny.