Learn to cut without mercy. If cutloss point is hit, cut immediately before you turn your loss into bigger ones.
But it can't be emotional move because of situation became scary for you at the moment. Only if such move was planned from the start.
Setting your cut loss is a good strategy for a trader because it can really help you on saving some money from the crash but don't panic easily look for some confirmation of a crash before you sold your holdings. Always learn from the crash don't make the same mistake again.