looking for help whit trading new to the game dont know how to do it.

in very new at pokemon diamond never played it before and discoverd that some poke can onli be acquired by trading and i dont know how if someone finished the game and is willing to help pls let me know.

You have what's called a "Pal Pad". There you have to register people's names and enter the wifi room.(Lady in Pokemon Center. She's upstairs in the middle). Enter the room and select the name of the person on the list when the log on also. There you can trade pokemon you have in your party.