1- We should check for similarities or plagiarism with other white papers, there are many tools available to check.
2- Search for information prior to the project about team members, social networks, jobs in other companies...
3- Direct communication with the team, if it is little or none, we must discard the project.
4- Ignore all the projects that promise impossible things like: Binance soon, big pump on the way...
5- Ask very technical questions of team members, scammers generally don't have that knowledge.
Those are some of the things I do, DYOR is the most important thing, and even then we are not 100% sure.