-Set the system date to your birthday, then talk to the nurse at a Pokemon Center and she will ask if it is your birthday. Answer "Yes" and she will wish you a happy birthday.
-Set the system date to your birthday, then go to the Pokemon Musical and talk to the owner upstairs to get the birthday cake. Relocator option: Go to the second floor of the building with the scientist that wants a password at Castelia City. Talk to him, then say "Everyone Happy" then "Simple Connection". Save the game. You can now use the "Relocator" option at the main menu to transfer the Legendary Trio (Raikou, Suicune and Entei) and Celebi to Pokemon Black or White. Easy experience: To easily gain experience, after you defeat the Elite Four go to the Giant Chasm with two Blisseys in the back of your party. After encountering the Ditto, send in Blissey. Let the Ditto transform into Blissey, then switch out and defeat the fake Blissey for easy experience.