Create a presentation you can deliver which is related to that product. The presentation should be helpful and useful, and mostly pure content. If the webinar is going to be an hour long, then you should have at least 45-50 minutes of good, solid content in there before you ever even talk about the product. An exception would be if the entire point of the webinar is how to use that product.
Let’s face it. Your audience has been conditioned to think “show me the money” by all the scams, gimmicks and otherwise sketchy products out there (and if not that, through Jerry McGuire movie quips for sure). If attendees still haven’t purchased anything several days after your webinar, they are probably thinking, “Your product sounds great, but show me real results from real people like me.”
For example, if you’re hosting a webinar on how to use WordPress blogs, and participants are asking a lot about increasing traffic, you could position your email like this: “I’m getting a lot of questions about boosting traffic to your blogs, so I’m throwing in a bonus how-to guide which will be sold later for $97, but you’ll get it free if you act now.”
"I invested $10,000 to learn similar content from another well-known industry leader a few years ago. I left Tamara's two-hour online workshop even better equipped and ready to take action to step up my game of leading successful webinars. Being able to learn the content and how-to information by webinar without having to drive or fly anywhere is a huge value. And I invested about $9500 less to boot! I highly recommend this training."
In December 2003, Citrix Systems acquired Expertcity, giving it the GoToMyPC and GoToAssist products.[29] The acquired company was renamed as the Citrix Online division of Citrix Systems. In July 2004, Citrix Online released GoToMeeting as its first generic web conferencing product.[30] In June 2006, GoToWebinar was added, allowing additional registration and reporting functionality along with larger capacity in sessions.[31]
Then you ask them follow up questions to make sure they understood your presentation, what they do not understand, what objections they may have, etc. etc. You will close more sales if you are able to get feedback from clients, and Webinars allow you to see their face, to hear their voice to know how they are feeling about you, your presentation, your company and your products and services.

Because a Webinar room allows you to communicate with your customers and employees better, and to get feedback from them at the right time, with the right information. This happens because a Webinar room allows you to enter a virtual conference room, talk (in your voice) and share pictures, web sites, Power Point Presentations and in some cases, any application on your computer, such as Excel, Word, etc. to tell a story or show people why they need your product or service.

Web conferencing technologies are not standardized, which has reduced interoperability and transparency and increased platform dependence, security issues, cost and market segmentation. In 2003, the IETF established a working group to establish a standard for web conferencing, called "Centralized Conferencing (xcon)".[6] The planned deliverables of xcon include:

Presentation of visual materials most often is accomplished through one of two primary methodologies. The web conferencing software may show participants an image of the presenter's computer screen (or desktop). Again, depending upon the product, the software may show the entire visible desktop area or may allow selection of a physical area or application running on the presenter's computer. The second method relies on an upload and conversion process (most commonly consisting of Microsoft PowerPoint files, other Microsoft Office electronic documents, or Adobe PDF documents).

Unveiled in 1996 by InSoft Inc., CoolTalk was a multimedia software tool that let PC users view data displayed on a shared whiteboard, exchange real-time messages via a chat tool or speak with each other via a TCP/IP voice connection. The product worked with Microsoft Sound System-compatible audio boards and was available in a 14.4-kbit/s version or 28.8-kbit/s version. CoolTalk was later packaged with popular Web browsers of the time.[20] CoolTalk 14.4 and 28.8 sold for $49.95 and $69.95, respectively, in 1996.[11][21]

Real-time text chat facilities such as IRC appeared in the late 1980s. Web-based chat and instant messaging software appeared in the mid-1990s. The PLATO computer learning system allowed students to collaborate on networked computers to accomplish learning tasks as early as the 1960s, but the early networking was not accomplished via the World Wide Web and PLATO's collaborative goals were not consistent with the presenter-audience dynamic typical of web conferencing systems.[8] PLATO II, in 1961, featured two users at once.[9]

Using Webinar software participants can share audio, documents and applications with webinar attendees. This is useful when the webinar host is conducting a lecture or information session. While the presenter is speaking they can share desktop applications and documents. Today, many webinar services offer live streaming options or the ability to record your webinar and publish to YouTube and other service later.