The Lifesling can be used in two ways. The traditional method is to drop it over your stern, let the 150 feet of polypropene line pay out while steering around the MOB to bring the tow line and horseshoe to the MOB. This is similar to bringing the tow rope to a water skier. Instead of needing pin-point accuracy, the LifeSling gives you larger window of opportunity to recover an MOB.
The new way to recover someone with the Lifesling is faster. Once some goes overboard, tack the boat and backwind the jib to stop the boat. Check for lines in the water, start the engine and return to the person under power. Pull abeam or slightly upwind and then toss the LifeSling to the MOB as if the LifeSling was a throw rope. This saves the time of circling the long line around. Keeping the boat 5-15 feet away from the person, which means you can use your engine without the risk of hitting the MOB with the boat or hurting them with the spinning propeller.
Watch this video for more tips on how to rescue a person in the water fast and safely.