It's important to keep the branding and design of your social media channels consistent with that of your website. Each network has its own specs for the background 'cover image' used on profiles. Below are some resources for templates that will help you ...
DDS
Google+
Official Social Media Logos
Over the past few years, Facebook, Twitter and Google+ have gone through some fairly dramatic logo updates. In some cases, the updates happen often enough that it's hard for designers to keep track of what the proper usage rules are for their branding. ...