This topic from last week looks helpful to those trying to fly under the ever increasing surveillance radar. http://www.theregister.co.uk/2015/11/12/snowden_guide_to_practical_privacy/
If you're just an average user concerned about your privacy
Use Tor when browsing.
Use an ad-blocker.
Use a password manager.
Use two-factor authentication.
Use apps that protect your information.
Use the HTTPS Everywhere browser plug-in.
Encrypt your hard drive.
Be smart with your security questions.
I have truncated the information shown here so go read the Register article for a much more informative set of suggestions, most are pretty much common sense but as always stay vigilant and try to minimise your privacy exposure on whatever platforms you utilise online.