public void Hit()
        {
            Hand.Add(GameDeck.GiveCard());
            Sum += (int)Hand[(Hand.Count - 1)];

            if ((Sum > 21) && (Hand.IndexOf(CardsValue.Ace) >= 0))
            {
                Hand[Hand.IndexOf(CardsValue.Ace)] = Hand[Hand.IndexOf(CardsValue.Ace)] - 10;
                Sum -= 10;
            }
        }