If you are trading in Options that means you are already in with RISK. But Still, you can minimize your loss by placing STOP-LOSS. Now, How do you do that? Place STOP-LOSS according to the risk you can take in a single trade.
For example, You have 1,00,000 in your Demat account and you take a risk of 1,000 - 2,000 per trade. That means in Options you are taking 30 - 40 points as a risk in Bank nifty and 15 - 20 Points as a risk in Nifty. Once you know how many points your Stop loss is, you can decide on the strike price and place an order. Remember this needs to be done quickly.
Now, you can slowly trail your stop loss or add more qualities once the position is going with you. It depends on the individual how they trade. I personally, add quantity and trail my stop loss to my entry price. Now, you got this right. You will automatically reduce your risk and increase your Reward.
Remember, do not overtrade if your stop loss is hit. Enter only according to your Strategy. Overtrading is where most traders lose their money.
Happy trading :)