You can sell it or you can hold it. Those are literally your two options. Since you can't make the market move, you can't save it that way. Best advice I have for you is does the project look dead? If it looks dead or heading in that direction I would sell my coins. If the project looks alive and fundamentals are well, I would hodl.
You only have to sell them if you are in economic difficulties, or health problems in these cases you must find a
adequate solution. On the other hand, if you have invested you must have patience and try to keep what you bought everything depends on
what coins did I invest?