EBay refund

[mats01_99]

Hi all. I've just recieved a shirt that I purchased from Ebay, however the description said that it was a Medium. The shirt is actually extra large. I had paid for this with paypal. I have sent the seller an email saying that I won't leave any negative as long as she accepts that she made the mistake and gives me a full refund. So, how do I go about this?, do I just send the product back?, will she be able to refund my paypal account? Should I charge for the postage as I live in Ireland, the seller lives in the UK so i'll be stung for a least 5 euro. Thanks all.