Eisenhower's approach, as both a general and president, was to assemble a very good staff and delegate, while monitoring how things were going. Staff, not line. Line managers in the military are unit commanders at various levels. Staff officers, derided though they tend to be, are extensions of the commander for whom they work. They have to be very competent but less ambitious than line commanders.
"The Hidden-Hand Presidency" (1982) is the best overview of how Eisenhower got things done. Eisenhower was probably the only person ever to be overqualified for the US presidency. Holding the Allied coalition together while winning WWII in Europe was a tougher job. As president, he was fairly relaxed and not overworked, while accomplishing an incredible amount.
He wasn't as laid back as people thought at the time. He wrote clear, incisive directives for his staff and Cabinet. It took a long time before Eisenhower's work was properly analyzed, partly because the Eisenhower Library is in Abilene, Kansas, and few historians wanted to spend a few years there going through the files.