Rahul, seeing the difference between your buy and sell quotes, I think you are doing fine. Since I do not look at option charts (just Nifty index), I cannot comment if it was optimal or not. But if you buy at support and resistance levels, wait for the IV to drop before buying (opposite for a short position). This way you maximize your profits and minimize your loss in the event of an adverse move. So make a habit of looking at IV values to get a feel of its expectation and gauge an optimal entry by looking at the movement of VIX. And shift to May contracts, but do look at April contract charts as well to get a feel of how quickly theta can kill your gains the nearer you are to expiry.