[Tohopekaliga]

Hmm, well. I play with a multitude of mods.

One that is very helpful is "Kerbal Engineer Redux." It gives you displays of the ship's deltaV capabilities, among other things. That's quite helpful, especially after looking up a deltaV chart of the system. You need ~4000 dV to get to orbit, then another 1000 to get into Mun orbit, and about 300 to get back.