Security in a volatile market

[Ted Leaman]

I am new to this concept, but for my entire life have been told that real estate investing is a must for a secure portfolio. However, with the history of the market and some of the new happenings and lendings, my question is this...

How do you invest in a way that is secure? I don't want to start collecting properties and get stuck with them and have all of my assets tied up in that. 

Is it better to buy and flip (while the market is good)? Is it better to buy and rent? Or simply get my license and try to sell properties?