See directions above to enter your W-2G. You can only deduct as much gambling losses as gambling winnings, but no more. You need enough itemized deductions (which include gambling losses) to overcome your Standard Deduction to benefit from your gambling losses. If not, you will take your Standard Deduction.
So, just enter your W2-G per the directions above, and TurboTax will compute the rest to your maximum benefit.
