to prove they're not scammer project and minimize your investment of being scam...
1. look for the team if they're legit and real human... prove to yourself if they're human and real, not fake linkin from russia, reddit or facebook stuff...
2. list your find...
I agree with that, but I think we should also see their project support on social media. If they have a lot of followers, chances are the project won't be a scam. Besides that, we need to study the road map and the whitepaper. If it's too ambitious and unreasonable, I think we better leave it and not invest. But if it makes sense, it could be taken into consideration for investing in the project