To choose a right ICO you can look for the feedbacks that they get from their investors or other option is look for the whitepaper that the full details that you will be needed is in their.
Well the strategy i do to find a promising ico is i always analyze if there whitepaper is good and unique because there are so many projects now that dont have a unique platform and many ico have always the same platform on other projects. Thats why only invest on ico that is popular.