How can I trade pokemon in my pokemon diamond rom?

I recently copied my rom and i want to trade pokemon through them. ive seen it happen in a pokemon emerald rom but i dont quite know if i can do it in my diamond rom. please help. thanks : )How can I trade pokemon in my pokemon diamond rom?you can trade using wifi but you cant since your using an emulator or you can just trade using people from the game like in snow point city a girl will trade you a haunter for a medicham you cant trade other than that.How can I trade pokemon in my pokemon diamond rom?POKEMON RULESSSSSSS!