Hi.
As I remember, your question relates to "Publishing Your App" section in Google documentation.
You can read:
Step 7: Provide store content
Using the dashboard edit page for your app, add the store listing information that isn't in the ZIP file, such as a long description, screenshots, videos, and links to related sites. See Supplying Images for help on designing the images for your app, and Branding Guidelines for information on how you can use Google brands.