Simply add multiple selections from any tab to create a bet. Open the betslip, enter your stake in the Bet Builder section and place your bet. Available markets can be seen under the Bet Builder tab.
The Betfair Exchange allows customers to bet against each other rather than betting against a traditional bookmaker. By matching customers, rather than taking the risk itself, the Exchange gives bettors the option to 'lay' (betting on something not to happen).