I think earn enough knowledge for this ICO which project you agree for investment. When you have enough knowledge about this ICO then you chose right decision for investment.
Its very important to have knowledge about the team who is bring the ICO. Also check the campaign if they are running and have they escrow the funds, are they paying the payment to participants on time, is the registered office in your country then you can go visit them as well which will give you more confidence and will get better vision about the project.