You go to the main menu and click on mystery gift. Then you select how you would like to receive the mystery gift.
wifi
Mystery Gift is already unlocked on HG/SS.
sometimes
Mystery Gift.
Mew
You have to be connected to wifi.
The mystery gift option is already at your disposal. Unlike in Diamond and Pearl, you already have the mystery gift option. Before accessing your save file, just scroll down to the mystery gift option.
The mystery gift option is already available in Pokemon HeartGold and SoulSilver. Before starting your save file, there is a menu option that says 'Mystery Gift'. It is already built into the game.
no ;)
Winners path is a pokewalker route given out as a mystery gift event.
If your referring to the pikachu colored pichu, then your out of luck because it was only available from march 5 to march 25 of 2010, through the mystery gift feature on Pokemon diamond, pearl, and platinum and then trade it to Pokemon heartgold or soulsilver.
lucky for u a mystery gift that is out right now will give u a jirachi