NASA studied several possibilities, including NASA's current program to send astronauts back to the moon by 2020, a more ambitious plan to skip the moon and aim directly for Mars and what the members called the "flexible path," which would avoid the "deep gravity wells" of the moon and Mars, saving the time and cost of developing landers to carry astronauts to the surfaces of those bodies.
A flyby of the moon might be followed by more distant trips to so-called Lagrange points, first to the location where the gravity of the moon and the Earth gravity cancel each other out, then to where the gravity of the Earth and sun cancel out. There could also be visits to asteroids or flybys of Mars leading to landings on one or both of the low-gravity moons of Deimos and Phobos.
The flexible path essentially goes across stepping stones" of progressively longer, more challenging missions by which NASA would learn how to operate long missions in deep space.
NASA may establish fueling depots in space. "You can now do much larger missions with the same size booster" by launching an empty spacecraft and fueling it in orbit.
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