Invest in combination with the Panic Index. Buy full positions when the panic index enters the extreme panic phase. After buying, do not care about the short-term price fluctuations, and hold until the panic index enters the greedy stage and then sell. There are at least 2-3 times a year when the panic index changes dramatically, so the operation should also be synchronized in about 2-3 times, simple and clear, easy to implement, and stable profit in the long run.