Step1: Click on the pencil tool within each webinar reading 'Edit/View Webinar details' 

Step2: Join the webinar by clicking on 'JOIN ROOM'

Step3: Click on 03 Dots at the left side of the corner.

Step4:Step3: Click on the tool reading 'SETTINGS' as indicated in the image below.

Here you will land on room settings where you will see the various options are given to customize your audio animations popups alert and many more.