Christmas gift for dog sitter?

Many clients give their sitters gift cards, cookies or even a bottle of wine, mine do. Any gift will be greatly appreciated by the sitter

That's lovely! There's no way of doing it through the Rover site. So your choices are to either give the sitter a check or cash at your next booking (as I do for my groomer) or to send it via Paypal or Venmo. You will need to find out the email account that your sitter uses for Paypal. Hope this helps.