Global Web Icons
These are the step by step instructions on how to add and global web icons on your site.
Navigate to Insert > Picture > (select the down arrow) From Address
Copy the URL below the image you'd like to use - exactly as it is displayed - and Paste it into the "Address" field. Next, add "Alternative Text" to describe what the image is (this text will not be displayed on your site; it is used to identity the object, particularly for those using a screen reader due to visual impairments). Once both fields are filled in, click "OK" for the image to be placed in your Content Editor web part.
(Continue ONLY if you are adding a LINK to a global image/button)
Select [click on] the image you have placed it your Content Editor web part, and navigate to Insert > Link > From Address.
Insert the URL into the "Address" field that you could like your new button to link to. Hit OK, and you're done! Don't forget to Save your work in SharePoint, or Publish the page when you're ready to make the new button and link active.
Global Web Icon Repository
Right Hand Sidebar (266px wide):
/Global Image Library/sidebar-images/contact-us-266.jpg (Use on right-hand sidebars - 266px wide)
/Global Image Library/sidebar-images/see-also-266.jpg (Use on right-hand sidebars - 266px wide)
/Global Image Library/sidebar-images/learn-more-266.jpg (Use on right-hand sidebars - 266px wide)
Left Hand Sidebar (300px wide):
/Global Image Library/sidebar-images/contact-us-300.jpg (Use on left-hand sidebars - 300px wide)
/Global Image Library/sidebar-images/see-also-300.jpg (Use on left-hand sidebars - 300px wide)
/Global Image Library/sidebar-images/learn-more-300.jpg (Use on left-hand sidebars - 300px wide)