If you want to tell the authentic ones from the scams, your best bet is to evaluate the team. If they are a bunch of never-heard-of nobodies forget about it, but if they are remarkable you might find the project minimally convincing.
Then you can evaluate the project itself, if their goals are realistic and achievable, if they are raising a proper amount and distributing the tokens fair, etc...
Right. And more reading about the project. Check also for opinions/blogs. Sometimes they help to assess the true nature of the project. But evaluate also if they are legit or just hyping them.