The act of shorting a token is betting against it; another way to explain it is that you can make a profit if the value of the token decreases.
To short EGLD, you can supply USDC as collateral and borrow EGLD against it. If someone borrows 10 EGLD, they would then sell the 10 EGLD for USDC. If the price of EGLD was to fall, they could buy back the 10 EGLD for less USDC, thus closing their borrow position and gaining the difference.
Step by step guide on how to create a short position
I) First of all, connect your wallet(1) and then select the USDC Money Market(2).