It's pretty easy.
- Purchase NIFTY BEES or any other NIFTY ETF worth 8.75 lacs (Currently, Nifty is at 17500, and the lot size is 50. So, to ensure that the covered call strategy is perfectly hedged, the underlying NIFTY ETF value should be equal to the Nifty derivative contract size. At the time of writing this answer, you will need to buy 4605 units of NIFTY BEES at 190 rupees each).
- Sell an Out of The Money (OTM) Nifty call option. (The margin requirement for 1 lot is approximately 76k. You can either pledge a portion of your NIFTY BEES to avail collateral margins or have sufficient funds to initiate the trade).
- Let's assume you sell 18000CE monthly expiry at the beginning of the month at the price of 100. If Nifty expires at 17900 (below 18000 strike price), you will make 10050 = 5k on the call option and 2.28% on the ETF investment = 20k. In total you'd make 25k in a month from an investment of approx. 8.75 lacs (2.85%).
- If you're looking for a higher ROI, you can implement the same thing by going long in nifty futures and shorting an OTM call option. Your estimated margin requirement will be 1.2 lacs and your max profit in a month is limited to 24% extending from the example used above. However, the downside risk will be much higher as it is a leveraged trade and an 7-8% fall can trigger a margin call/broker square off (Whereas if you did it using an ETF, you can hold without worrying about margin shortfall). You can learn about the margin requirements here88.
To learn more about this strategy, I recommend you to read this chapter on School of Stocks150.