Via Bruce Schneier, an advisor to the project, Citizen Lab has created an online tool to help you stay safe online:
Security Planner is a custom security advice tool from Citizen Lab. Answer a few questions, and it gives you a few simple things you can do to improve your security. It's not meant to be comprehensive, but instead to give people things they can actually do to immediately improve their security. I don't see it replacing any of the good security guides out there, but instead augmenting them.
The advice is peer reviewed, and the team behind Security Planner is committed to keeping it up to date.
Some of the recommendations are simple: use Chrome; use https:// whenever it's available; use your computer's built-in encryption (BitLocker on Windows and FileVault on Mac). Some are a little more complex: use two-factor authentication; set up a password manager.
I recommend anyone who uses computers do a quick self-exam with the tool—especially if you aren't that experienced with security.