I usually look at:

1) The idea of the project. It should be worthy and smart enough. This is one of the key features of every ICO.

2) The team. Who are these guys? What background do they have? What portfolio?

3) The website. Userfriendly and modern design. Is it good looking at least?

4) The whitepaper. It should be detailed enough and look seriously)

5) The news and results of past rounds/private sales. Are the devs doing anything now? How much have they already collected?