The down trend will continue, wait for some short term uptrend and then let it break the uptrend line and enjoy the fall. You can see the spot chart and trade in options right after the trend line is broken. for stoploss or target use this chart.
If SBI breaks the pink line, go long, until then wait for SBI to respect the price action trend line. If it doesnt break, you can short when it touches the line. (ONLY INTRADAY, DONT HOLD FOR SHORTING)
Wait for the price to cross the line, If it goes up, go long. If it goes down, wait till it makes double bottom at the downside, and then it will go up at the end. But don't buy until a confirmation is made at down.