It's the same as doing stocks, it's the same as doing long, but on the contrary, one buys more and one sells short.

~ sell ~ open position ~ fill quantity price

If the price is below 3730, what is the transaction cost?

For example, short at 3730, and when it falls to 30 15, it will earn the difference of 15 (I don't know how many tons of soybeans are in one hand ... I only make Shanghai copper ...)

If the current price is 3730, if you fill in 37 15, the system will close the transaction according to 3730, and your cost will still be 3730 (long and short will close the transaction according to the most suitable price of the customer).

If you still don't understand

You can use the simulation software to operate once and you will understand ~

In addition, futures are absolutely risky and do not play with capital.