To place a Bet Builder simply tap the Bet Builder option from the tabs along the top of your desired match screen as shown in the West Ham v Southampton example below, this will display all available betting markets for this match.
Placing a bet builder is easy. All you need to do is find the match or sporting event you want to wager on, and click on the 'bet builder' tab at the top of the listing. If there isn't a 'bet builder' tab then you can still add multiple selections in your bet slip.