Turn off the breaker controlling the sump pump to prevent any electrical discharge. If the pump is malfunctioning, it could start acting erratically. If the pump isn't working due to power outage, use a battery-powered pump to empty the water from the sump pit.
Drop the intake hose of a water pump into the sump pit so it is submerged.
Run the outtake hose somewhere that can handle the water flow safely. This location should be far enough away from the house to prevent the water from flowing back toward the foundation. The hose should have as few bends as possible so water flows smoothly and the pump runs efficiently.
Turn on the pump and run it until the sump pit is fully drained.