The Facebook Cover Photo is one of the best ways to add some personality to your page. It's hard to miss--it's the large, wide photo at the top of your timeline.
Cover photos are always public. So even if you lock down all the other privacy options on your page, everyone is still going to be able to see the cover photo.
And it's the first thing visitors to your page see, so it's a good place to set whatever tone you want to set. You can use a photo of yourself, a photo of a place you visited, or maybe something more abstract.
Facebook Cover Photo Dimensions
The cover photo will display at 828px wide by 315px high. You can upload a photo that's already at those exact dimensions, which is ideal.
If you're planning to use a smaller image, it must still be at least 399px wide and 150px high. Anything over 720px wide and 150px high should work well.
If you upload a larger image you'll be given a chance to move the reposition it by dragging to choose the crop you'd like displayed.
Privacy Controls On Old Cover Photos
Because cover photos have to be publicly accessible, you can't control privacy settings on the photo that's currently active. But if you replace one cover photo with a new one, there's now a reminder that you can change the privacy settings of those old cover photos.
How to Change a Cover Photo
When you're logged into Facebook and go to your page, roll the cursor over the cover photo. You'll see a new "Change Cover" button appear. Click on that and choose where you want the photo to come from, whether that's a photos you've already uploaded or a new one that you want to upload. (If you need to reposition the photo after saving it, you use this same button.)
Using a Collage
You can also create a collage in other software and upload it as a single image file. Here's an example:
You can find more examples on my guide to making Facebook Cover Photo Collages with Lightroom.
Using Logos and Text on a Facebook Cover Photo
When you upload images, Facebook automatically applies some pretty aggressive compression. It makes the files much smaller so that the page loads more quickly. And it can also degrade the image quality of the photo.
If you're using text, logos, or watermarks on your images, that aggressive image compression can make them look blurry and ugly. But there is a way around it. Take a look at my post on using text, logos, or watermarks on Facebook images.
What You Can't Use for Your Facebook Cover Photo
Photos of yourself are fine. Photos you've taken are fine. But there are some things you can't use: "Cover photos can't be deceptive, misleading, infringe on anyone else's copyright or be in violation of the Pages Terms."