Yes, it's hard to believe that we actually need to provide such information on a Homeowners' Association website, but it's a brave new world we live in.
DHS has produced a very good video about an active shooter situation titled Run, Hide, Fight. Things to note is that these incidents evolve quickly and are dependent upon circumstances. The DHS video can be seen here. DHS has also produced a downloadable pocket guide.
A general suggestion is to do what FCPD Officers are trained to do, which is to always be vigilant and play the “what if” game in your head when going somewhere: What if this occurs? What are my escape routes? Where is the nearest cover (something that would stop a bullet or the weapon being used)? What could I defend myself or family with? Do I have means of communication, such as a cell phone? Break down the elements and think through the what-if questions in your head when going somewhere.
Bottom line: always be aware of your surroundings and pay attention to people in your vicinity. Keep alert. Stay alive. If you find yourself in an active shooter situation, decide: run, hide, or fight. Whatever you decide, commit to it.