There isn't a way toa dd 'Social Plugins' (like Wordpress or Blogger plugins) to your profile page as HubPages doesn't allow access to the root HTML code or file directories on their website.
What you can do is setup social media profiles and include links from your HubPages profile (e.g. Twitter, Facebook, Google+, LinkedIn, Pinterest etc.)
More importantly, you should include links from those other social networks back to your HP profile and articles.
I have written an article on how to get more traffic to your hubs here, I hope you find it useful: http://paulmaplesden.hubpages.com/hub/A-Quick-Guid...