There are really no specific guidelines towards finding scam coins. Basically, there are just a few tips and tricks people tend to follow to help them what coin is safe to invest and what coin is not, and mostly scam. Research and knowledge are two weapons to equip yourself with in order not to fall for the scam coins.
but in order to earn the skill of high-quality research of coins and to get the knowledge for this, you need to get a lot of experience, which will not always be pleasant
ICO and airdrops are a hint that the coins are mainly going to scam people in the end.