How do I trade over the internet on platinum?

Question

i just got a 3DS and I need a phione to complete my pokedex

Answer 1

Here's how you trade Pokemon over the internet via GTS:

1. Go to Jubilife City
2. Go to the Global Terminal.
3. Head to the north-western counter
4. Deposit Pokemon in the GTS

Here's how you trade Pokemon with yourself (you need 2 DSes)
1. Insert the game you want Phione in one DS, and the game that has Phione in another.
2. Go to the second floor of any Pokemon Center
3. Talk to the lady that trades over Infared connection on both DSes.
4. Connect both DSes and trade Phione over.

Answer 2

You need a WEP key internet. WPA/WPA2 does not work.
Go to the main menu wherr it shows giritina. Press a. Press A on internet settings. Make a new internet connection . To do this, choose a available slot and search for a connection. Get your internet and enter your WEP key.
Hope I helped.