Crucial to recovering the crewman who's fallen overboard are getting buoyancy to him, keeping him in sight, heading the boat back to him, stopping safely alongside him, making contact, then getting him back aboard. These steps include using the Lifesling. This MOB device and the procedure to use it, developed by the Sailing Foundation of the Pacific Northwest, is recommended by US Sailing and is considered the leading method for a lone crewmember to retrieve someone who's fallen overboard.
To rescue a crewmate, especially if you're alone, you should know how to:
1. Put a line on a cleat and lock it.
2. Tie a clove hitch and a bowline.
3. Heave a throw rope into the wind.
4. Heave a throw rope a second time without restowing it in its stuff sack.
5. Perform pre-start checks and start the engine.
6. Tack and jibe as both helmsman and sail trimmer.
7. Make a Lifesling recovery, both in port (whether at anchor, on
a mooring, or at a dock) and while under way (sailing before the wind in light or moderate conditions).
8. Create a crew-overboard search plan.