Louis Jordan's three-paragraph statement says he stayed inside the cabin to keep dry and avoid sun, wind, waves and sea spray.
"Every time I went outside, I exposed myself to getting my clothes drenched, which would have made it harder for me to keep warm," Jordan said. "My blankets were already soaked, and often there was no way of hanging up my clothes to dry. Keeping dry was vital to my survival."
Jordan also says he set up a makeshift mast with a small sail to get the boat headed in a westward direction.
He says he rationed food and water and kept his calorie expenditure low.
"That meant I had to stay inside the boat as much as possible, therefore I didn't have a sunburn, or blisters, as if I were found clinging to an upside-down boat," Jordan said.
Jordan was spotted by a German-flagged boat Thursday, more than two months after sailing out of a South Carolina marina. Coast Guard crew members who retrieved him said they were surprised by his fit appearance and overall health.
Thomas Grenz, the captain of the German tanker ship that spotted Jordan last week and brought him aboard, said Jordan's U.S. passport described him as weighing 290 pounds, but he was probably down to 200 pounds when the crew found him.
Officials with the U.S. Coast Guard say it wasn't clear how long after he left the marina in Conway, South Carolina, that his boat first capsized. Jordan's sailboat was upright when the German boat found him.
Jordan told his family that he was going into open water to sail and fish, according to his mother, Norma Davis.
He told WAVY-TV that he was sailing north when he encountered bad weather. He said he saw a wave crash into his window and that his boat eventually filled with water.
The Coast Guard began a search on Feb. 8, but it was abandoned after 10 days. Some sightings of Jordan were reported by other sailors, but they couldn't be confirmed.
Jordan's statement thanked the Coast Guard rescuer who dropped down from the helicopter to lift Jordan off the boat. He also thanked Grenz and his crew for turning their ship around to save him.
"Their sacrifice demonstrates that our basic humanity is to care for and protect one another," Jordan said. " I'm grateful for all of your support and for your honoring my story. I'm writing a book on it now. All the glory goes to God for answering my prayers so perfectly. God is truly great."