It is very difficult to know if the ICO is a scam or not, maybe I can only say look from the ICO manager, whether he has ever undergone ICO and whether the ICO is successful or not,
looking for a reputable manager is a good way to minimize the risks of being scammed but it isnt guaranteed that you can avoid all scams in the long run . its hard to detect scams on an ico because all of them are the same , they dont pay thier participants upfront but rather they only pay after thier ico ends which usually takes three to four months . there are aalso alot of factors that can affect the success of an ico and that makes them to be riskier than investing or trading a crypto .