When creating your event you will be asked to enter a description that will display under the 'About' heading on the homepage of your event.
Should you wish edit or format this text you can do so post creation.
To edit your event description:
From your Dashboard, under the Manage Event Overview heading, click on your event name
From the left menu, under Basic Information, click Homepage & images
Click on the Edit Homepage Information tab
Under the About heading you can edit and format the text using the text editor
Click Save