2. Choose a Unit Size
Once you’ve set aside a set bankroll amount, you need to determine what percentage of your bankroll you will wager on any one event. For beginner bettors, we recommend that you keep the size of your bets consistent: Select a unit size somewhere between 1-5%.
Conservative sports bettors should bet 1-2% of their bankroll per single bet. In contrast, more confident and aggressive bettors may consider betting 3% of their bankroll. If you’re extra confident in your sports betting knowledge and skills, then it’s possible that you could increase your unit size to between 4-5% of your total bankroll.
https://www.sportsbettingdime.com/guides/betting-101/money-management/