First, you will obviously participate in the webinar online. That means you will need to have a computer with speakers, and a camera/mic - if you plan on interacting with the other participants. Most of the time participating in a webinar is very straight-forward. The organizing party will plan a schedule for the webinar, which includes presenters - often a time for questions and answers - and possibly open it up to other participants online who want to share information with others. Most webinars allow you to just sit back and watch the presenters. That means you won't (likely) have to talk to others online if you don't want to. However, you should contact the webinar's organizing party to find out what they want of participants. That way you can know (for sure) what to expect when you start the webinar.