If you're using a laptop/desktop PC to change the odds, you should click on the box in the upper right-hand corner of the screen. After clicking on it, it will expand and show you the available odds formats.

However, if you're using a mobile device, you should click on the ‘Bet slip’ button that is at the bottom of your screen. Then you'll be able to click on the box with the available odds formats and select the format you want.