ive just had to do this for roulette, deposited 300 off me credit card on wed, and now i've just withdrew 2k
the winnings HAVE to go on the card that the initial deposit was made on, this prevents fraud etc. withdraw it to that card, and if like me its a credit card you usually have to wait 3-5 days for it to "credit" the account, contact your bank, and when the amount has cleared they should transfer it to the credit-card linked bank account (if that makes sense) that may take another 3-5 days and then you should be able to withdraw the amount
hope this helps!
(the account was with ladbrokes)