I have friends who are doing contracts. I want to ask a question about how to vote when going long or short.

I see that the market is weak today and I want to go short. There is no problem with the entry point, but the problem lies in the votes. My thinking is like this. If I want to go short, I choose the weakest ticket, which is The ntra that fell the most that day, but I found that even if the market plummeted, this stock did not fall very much. Instead, it was the strongest among my own votes. That is, the stock that rose the most was the shi coin, which fell very much. Big, but the problem is that with such a strong ticket, I am afraid that it will directly pull up, so at some support positions, I directly reduce most of the position, resulting in not eating much meat? I would like to ask, when you go short or long, how do you choose the tickets?