Hi Tfence,
You can't send credits directly to someone else, but you can send just about any item in the Pro Shop (Master Tier items excluded) to another player as a gift. Just browse the items available and you'll see the blue GIFT button on the item detail screen next to the purchase button. Just click that, fill out the username of the person you wish to send to and it'll go directly to their inventory with a note letting them know they received a gift.