To protect our trading capital, we need to protect our trading capital, our trading capital must be kept in a good level, if our trading capital level is drastically then the capital's ability to get profit will also be drastically reduced, besides the effect on Psychological trading will also affect our next trading trip. We also need to protect our trading capital from the worst possibility, MC, so it is necessary to not medivate all our trading capital, some of the trading capital should be stored as a capital reserve