Just tell him you are trading internet currencies, and making some money doing it. You can wire transfer but the fees are higher and it takes 3 days, but with the way you are doing it you will have the virtual currency in a couple of hours. If he's interested in bitcoin, saying something like "it's the way of the future, especially for buying stuff on the internet. Some companies are even giving discounts when you use them". blah blah. act excited about bitcoins (or if you actually are, as I am, just be yourself and shoot the shit).