Now its very difficult to distinguish scammers from really worthwhile projects, here you need to understand smart contracts, how they are written, and when and in what volume they return their coins. As far as I remember, there is even a project for checking counterpacts, called CertiK, but so far it has not started, I think he will make our life easier.
What kind of project? where to find and read it? It would be very good if the professionals were involved in project verification, in our life there is a lot of scam.