Cover images must be at least 399 pixels wide and may not contain:
Price or purchase information, such as "40% off" or "Download it at our website" Contact information, such as web address, email, mailing address or other information intended for your Page's About section References to user interface elements, such as Like or Share, or any other Facebook site features Calls to action, such as "Get it now" or "Tell your friends" To get the best quality image and fastest load times for your Page, upload an sRGB JPG file that's 851 pixels wide, 315 pixels tall and less than 100 kilobytes. All cover images are public, which means anyone visiting your Page will be able to see the image you choose. Covers must not be false, deceptive or misleading, and must not infringe on third parties' intellectual property. You may not encourage or incentivize people to upload your cover image to their personal timelines.
The cover page Cover photo like a magazine you can’t advertise just brand so you need to use the timeline. The time line starts right under the cover photo on the left
You can upload a JPG, GIF, or PNG file. If the image is larger than 111x74 pixels, it will be resized and converted. File size limit 5 MB. If your upload does not work try a smaller picture.