The term “selling short” is often misunderstood. When you sell a stock short, you are never the owner of shares of stock. Instead, you are borrowing the stock and immediately selling it. When the price changes, hopefully to a lower one, you buy back the stock and return it from where you borrowed it. The difference between the high selling and the low buying is your profit, minus fees and commission, of course.
In currency, selling short is a different animal. You never actually can sell a currency short; instead, the term refers to the act of selling off a currency. So when someone says they are going short with a currency, they are actually selling it in exchange for another. The same transaction has you going “long” in the currency you are purchasing. This is not the same as the Part Time Gold Trader. When you trade gold, you are actually hoping the price of gold drops.
Of course this is just in the straight forex market. There are exchange traded funds (ETFs) out there that you can sell short. Many ETFs are linked to a currency, so if you wish to sell a currency short in the traditional manner, you will need to find an ETF linked to the specific currency and short that. There are also several inverse ETFs that exist. If you don’t want to short an ETF, you can look for an inverse of the given ETF and buy that with a long position. When the normal ETF goes down in price, the inverse will go up, leaving you with a profit. ETFs might seem confusing at first, but they trade just like shares of stock do.