The first step in rescuing a crew overboard is preparation. You should have a well thought out AND PRACTICED plan of approaching a man overboard and a method of hauling the individual on board.
YELL Crew-Overboard Water to alert all crew members.
Throw several flotation devices to the man-over-board. This will not only aid in the flotation of the COB but also create a debris field which will aid in keeping the COB in site.
Once a sailor falls overboard, one or two crew members on board are assigned to be spotters and are to point at and not to lose sight of the overboard sailor. The position of the sailor and time should be marked on the chart and/or GPS. If there is a current the position of the man overboard will change with time.
Depending upon the number of crew left on board, one may have to let go of the jib and maneuver with the mainsail alone.
Unless there is insufficient wind, most authorities recommend resisting turning on the motor. Remember, the sails will continue to power the boat and stopping the sailboat with the motor running and sails up may be difficult.