Login to your DEMAT and trading account , look for the Futures and Options tab and follow the steps by filling the form. You can find the place order or similar tab where you must enter the stock code (available on the internet). You will find the different F&O trading contracts, and you can choose one by clicking the buy/sell link. You will be redirected to a new page where the basic contract details will be auto-populated, based on whether you choose Futures or Options Trading. You must decide the order type - market or limit order, order validity period or maturity date, limit price, and stop-loss trigger price. Once you enter these details, your order will be placed.