Build stable rocket with an atmospheric, orbital, lander/return stage.
Fly rocket up till apoapsis is about 100,000m~
Wait till you're about 30-60 seconds from your apoapsis and fire your rockets to your right (90 degree mark)
Once you're in a circular orbit, wait till the Mun rises over the surface of Kerbin, they should almost be lined up:
.......Mun\ <--- Rotating around Kerbin counterclockwise
......Kerbin\ <--- You see the Mun "Rise" over the surface of Kerbin
..........You\
Then blast off, you should run into the Mun's sphere of influence.
Landing is the hard part.
When you're about 100,000m off of the Mun, do a burn at full speed for a second or two to see how fast you can slow your decent. Then gauge that with how fast you're losing altitude and try to only make one or two big burns to save fuel. Try to touch down as slow as possible. RCS will help you lose any lateral speed you may have here. (jklihn keys)
Welcome to the Mun.
If you'd like to return, you need at least a half tank of liquid fuel. Usually you can get away with simply blasting straight off of wherever you landed and fall into Kerbin's sphere of influence.
