I always do a research on coins, especially the ones I get. Even then it's hard to decide what to do. I wouldn't recommend selling. Only if particular coin got pumped and it will lose some value later. But you need to track the development and forum. Holding is the best option because you can get better value later for received coins.
There is not a stock answer that we can give for every single case, so you need to make a research if the coin you got is any good then it could be a pretty good idea to keep holding your coins for as long as you can but if it seems that the coin is not doing any good after the ico it may be a good idea to sell before the price crashes to zero.