She didn't. A lady named Mrs. Pryor, who had power of attorney for her estate, did. A quote from an interview with Mrs. Pryor....
"Winding down the interview, McConnell asked: “Would you say that Ayn Rand practiced what she preached?”
Pryor replied, laughing: “Yes, that’s why I had so much trouble with her.”
“You mean the Social Security issue and all that?” McConnell said.
“Yes,” Pryor said."