Yes, never trade the whole money you keep. Always think about your family, always spare a money for them. Some greedy peeps are investing the whole money, selling their house just to buy Bitcoin.
I think the most secure trading is to use some money from trading capital and use money that will not be in use for the near future,
for example I have $ 1000 and I need to use the money for my family's living needs, then I can use $ 250 for trading and the rest to survive, do you mean from this revelation?
this method is used so that you are not too depressed if the money you have stuck in the expensive price.