How do i get my friend id for pokemon diamond to trade?

Question

yes, ive beaten elite four. i want to trade wifi. how do i get my id and do specific trades?

Answer 1

im pretty sure u have to connect with a friend  and then if they have wi fi u play with just them its wierd im not pretty sure thats how it works

Answer 2

After you've defeated Roark and obtained your Coal Badge, go to any Pokémon Center and go downstairs. A lady behind the counter will speak with you and give you the Pal Pad key item.

Once you've obtained that, simply go into your Bag and use the Pal Pad. You'll have an option to view your own Friend Code, view your Friend Roster, and to Register a Friend Code.

If your Friend Code isn't availabe, you'll need to connect to the Nintendo Wi-Fi Connection first, which is done by going to the other ladies behind the counters and entering the Wi-Fi Club.