There are lots of benefits to contributors uploading a profile picture (also known as an Avatar) to your WordPress site: it makes it clearer who is writing each blog, it helps the writer feel part of your site, it makes your site more personable and friendly which helps your readers to engage more.
WordPress, by default, uses “Gravatar” for profile pictures – it’s an external avatar hosting service owned by the same folks who own WordPress.com. I am not a huge fan on Gravatar for a multitude of reasons, but for now, lets just say that I think for most sites it’s just better to let users upload their own. It won’t use much diskspace or bandwith on your server, you have control over what images are being displayed on your site, it’s less complicated for your less technical users and you can help them to change their image later, if they get stuck.
Here is a quick how to guide for getting this set up on your site.
Install a avatar plugin
I use WP User Avatar, it’s simple and has good reviews and a lot of users. There is a premium version (I am not a fan of that model in general) but all the features most people need are in the free version. Once installed and activated, go to Avatars > Settings in the menu and configure it like this:
Remove the avatar link in WordPress
Your contributors will now be able to upload an image from their profile page, which is found in the top right dropdown menu from their dashboard, or at www.example.co.uk/wp-admin/profile.php. However, there will still be a link under the image to gravatar. You can remove this by adding this code in the theme functions.php (of your active theme)