you will most likely have to give them you address details in a private message and the method you want to pay, and you should get a reponse with there bank details which u might have ot print of and take to the bank they have account with the details should also have a refence number on thats linked with your name and address so when they recieve the money theyshould send the projumps out the next day or to. just make sure to get a receipt for the bank deposit as well.
but then again i might be wrong
note: remember to specify the weight of the ones u want to