I have three step rule that I always follow. I take a look at the developers and owners and basically the team of the ICO first. I do research on their names and try to see how important those people are and how involved they are and how reachable they are. If they are good people with great CV's and successful things in their past and they are constantly involved and you can reach and ask stuff thats a plus.

Second is the feature or problem solving, if a coin is coming out that means they are trying to add a new feature to that coin or at least try to solve a problem, if I think thats valuable thats another plus. Third and last is the community, if the community behind is really going crazy and hyped about it, than thats another plus. If a coin gets three plus than I decide to invest to it.