Enter the BetMGM bonus code when you join BetMGM Sportsbook in Maryland. You will get up to back in bonus bets if your first bet loses.
If you'd rather not have to risk so much to get a large bonus, you can use the BetMGM Sportsbook bonus code GETPLAYMD, and you'll get a Bet $10, Get $200 in bonus bets welcome bonus. The choice is yours.