Safeguard your privacy
It is very important that you safeguard your personal information and private life.
These websites offer some suggestions:
http://www.insidefacebook.com/2014/08/11/lock-down-facebook/
http://www.tomsguide.com/us/lock-down-twitter-privacy-settings,news-18865.html
NASUWT guidance
http://www.nasuwt.org.uk/InformationandAdvice/Professionalissues/SocialNetworking/NASUWT_007513
Worksmart from the TUC - the umbrella for Britain's unions.