Wait about three hours for the recently poured cement sidewalk to dry naturally and cure partially.
Immediately cover the partially sidewalk with sheets of plastic. Hold down the ends of sheets with wood planks. Position the planks so they are off to the side of and not resting on the cement surface.
Leave the sheeting on the cement overnight, then remove it and spray the sidewalk with a light mist of water until it is damp to the touch. Once you have sprayed the cement, immediately cover it again with the plastic. Perform this once a day over a period of five to six days.
Remove the plastic sheeting after the fifth or sixth day and allow the sidewalk to cure for 48 hours before using.