Many of our client sites don’t have the luxury of a CDN with their hosting, so we are always looking for ways to delegate the hosting of assets to reliable third party CDNs like Google CDN or CDNJS in order to boost load times. The great thing about CDNJS is that they host a large variety of assets that you won’t find on Google CDN, and it’s easy to find minified versions of a current library and serve those assets using the SPDY protocol. If you don’t find a library in CDNJS, you can always submit a library yourself via GitHub. There is even a CDNJS Plugin for WordPress.
Use the YSlow and PageSpeed Insights browser extensions to analyze the performance of your site and to provide suggestions to make things faster. WebPageTest is another great tool for checking your site’s performance.