The best way one can avoid scam ICOs is by doing thouriugh research and also follow up team to know how genuine and authentic they are if not, we may end up failing inside pit always. I also tell people to follow there minds by investigating rather than going by news from people as news fly's everywhere and people pick without cross checking. Know what you are going in by yourself so as not to miss out.
Doing a research should not be done for a day only, it should take time, so for me maybe less than a week or a week will do as you need to be involved and ask everything that is not clear to you in their whitepaper, and it is so important how they are going to fulfill it. SCAM ICO's are very clever too, so let's always check how are we going to make the kind of investigation we need.