you must ENSURE that you have Wi-fi connection, and should probably test
this with a pokemon you don't like first.
Go to to the Global Trading Station (GTS). And Log in.
Once your in the main menu of the Global Trading Station. Go to "Deposit". Put in the pokemon you want to clone.
Deposit the pokemon into the GTS, make sure you offer it
for a Pokemon that nobody would trade for it. Cause if someone trades for the
pokemon in the GTS, Then the whole process is ruined.
This is the hard part. It should even be considered as the main step
into duplicating your Pokemon.
After depositing your Pokemon It will now say: "Checking GTS's Status...."
On the right of that message, a clock should be going around. On the eighth
spin, simply turn the DS off.
It doesn't have to be exactly 8 spins!
Your goal is to shut your DS OFF 1 spot before the loading is complete.
Turn your game on. You should get a error message:
"Your file has been corrupted. The previous file will be loaded"
Don't worry. This is normal.
Go back into the GTS, and you should have one in your Party, and GTS slot.
Logout and save.