Use this long-form section to actually paint a picture of the before and after. What's the problem you're solving? What's the benefit people are getting?
For example, if you're hosting a webinar about how to collect leads for an online business, describe the struggle of trying to find and convert prospects—then explain how your webinar is going to help make it easier.
You can also highlight the urgency or exclusivity of your offer. If this is only available on a particular day or for a limited time, make that clear.