Definitely do YOUR HOMEWORK!  I've invested in many ICOs myself and am very glad I did, but only after doing my own research.  You need to read the white paper for every project you consider. Learn about the experience of the team behind the project.  And only if you are excited about both of those things should you even consider an investment.

I'm part of a group doing its own ICO now so I'm on the other side of the fence at the moment, but I wouldn't want anyone contributing money to our token sale unless they fully understand what we are doing and believed in its long term success. 

Best of luck to you!