Hill was no rookie agent when Kennedy took office on Jan. 20, 1961, with has first assignment having been protecting President Eisenhower.
"We had a wonderful time working with him," Hill said. "He was a very congenial man."
Hill spent much of his presentation talking about how different Mrs. Kennedy was from previous first ladies.
"Mrs. Kennedy wasn't like the other First Ladies," Hill said, adding that the First Lady was an accomplished horsewoman who also served as a goodwill ambassador for her husband on overseas trips.
"Mrs. Kennedy was very adventurous," he said, recalling the time when she and her sister, Princess Lee Radziwill, hopped aboard a camel on a trip to Pakistan.
"First, they got on the camel. Secondly, they got to riding it. Then, she takes the reins and swats him on the rump and they move on.
"The Pakistan officials were scared to death."
After sharing more anecdotal information, Hill talked about that fateful Texas trip that ended with Kennedy's assassination. All went well, he said, until the motorcade through downtown Dallas.
"There was a very sharp angle between Houston and Elm Streets where you really had to slow down," he said. "I was in the first car behind the President and First Lady.
"I heard this explosive noise over my right shoulder," he said. "I saw the president had grabbed his throat, so I jumped off the running board to get on top of the rear of their car.
"As I ran, I heard a second shot. As I approached, there was a third shot."
Hill recalled that President Kennedy couldn't duck out of the line of fire because of the back brace he was wearing, putting him in position for the fatal third shot, which destroyed the right side of his head.