Things You'll Need
Instructions
Play through Pokemon SoulSilver until you receive the first gym badge. You cannot trade Pokemon until you have earned this badge.
Navigate your character to a Pokemon Center in any major town. On the town map, the symbol of a Poke Ball denotes them.
Go to the upper floor of the Pokemon Center and speak with the woman at the middle counter to enter the Union Room.
Enter into the Union Room in the same manner on the DS console that contains the Jirachi save. The two Nintendo DS consoles must be near one another to trade at the Union Room.
Press the A button while facing the other character that appears in the Union Room to speak with them.
Select "Trade" from the talk menu.
Choose the Pokemon that you would like to trade for Jirachi and confirm by selecting "Yes."
Choose Jirachi on the other Nintendo DS console, and select "Yes." to trade your Pokemon for Jirachi.