If he think that the coin he have, has a great potential then hold it for quite sometime and wait for the right timing, when value increases already and the market is in good condition too then that's the time to sell your coin orvided that you have a good site to treade your coin and is legit so that you won't regrets it later on. just be wise though.
Apart from holding it we also need to analyze market movements however it is an important thing,
and in holding coins I think we have to really be patient,
Obviously holding a coin isn't that easy and hopefully he can