I'd hold off until this evening to do anything. Before going to bed, candle to ensure you are not going to poke the duckling, then pop a little safety hole through the shell and membrane into the air cell. I use a glasses screw driver, but many use tiny drill bits or screws. Place the egg back in its original position, and leave it for the night.
Calls are like torture to hatch! They take about 3 days... TORTURE.
Calls are like torture to hatch! They take about 3 days... TORTURE.