Shorting means you expect the shit to go down in value. Usually to short something you borrow a stock from someone (not everyone can borrow stocks), pay the fee to the source, sell it for 100, wait, buy it back for 90, give it back to the original owner. You made 100 - 90 - fee.
Borrow 1000 usd from a bank (1), sell if for your target currency (2) that you think will raise compares to usd, wait, exchange 1000 usd from the target currency (2) and give it back to bank + rates (1).
Shorting means you expect the shit to go down in value. Usually to short something you borrow a stock from someone (not everyone can borrow stocks), pay the fee to the source, sell it for 100, wait, buy it back for 90, give it back to the original owner. You made 100 - 90 - fee.
Borrow 1000 usd from a bank (1), sell if for your target currency (2) that you think will raise compares to usd, wait, exchange 1000 usd from the target currency (2) and give it back to bank + rates (1).
What is left over in currency (2) is your profit.