There is no need to long essay here. Just look at these few essential things, which should be part of every legitimate project, that is asking for your money. This is especially the case of ICOs. Many of ICOs i saw lately are outright attempt to scam people. So be careful.
1.Do not judge quality of ICO or coin based on quality of webpage. Many great coins have ugly pages and vice versa.
2.Look for list of members of development team, with names. You should randomly cross check them on social media.
3.Is there some headquarters address, or some form of contact?Also is it on social media, not only telegram?
4.There should be whitepaper available on project page. Read it before you make investment!Does it make sense?
5.Try to google other peoples opinions on project. Can you even find something?
6.How aggressively are they pushing you to buy coins? Good legitimate project doesn't need to do that.
If you have any doubt, don't invest. Better to miss out, than got scammed.
You are all very welcome to add your own tips. I hope this will help someone.