The total number of bookings is a market where you guess the number of yellow or red cards to be received by players within the match's regular time. This bet type often comes in the form of Over/Under. For instance, the operator may require you to predict whether the total number of bookings will be Over/Under 3.5.
Right underneath the typical Place BET" button, a corresponding "FREE BET" button will appear. In order to place a bet with the Free Bet, you must first press on the "FREE BET" button and then press on the Place BET button. You must wager the Free Bet one time.