Read the white paper, meet the team if possible if based in your city, understand the project on which they have introduced the coin and their future and usability in coming years. Also see if they have any bounty or promotion happening and how are they being treated with answers of the questions raised. Also are they paying regularly to their participants or not. If you feel comfortable after doing your own research and with this points you can invest in such projects right at the beginning of the PRE - ICO stage to get the better deal.