Kerbal Space Program

OK, so this one isn't too bad. Does not need to be in Career or Science, Sandbox mode is fine. Start up by going to the Vehicle Assembly Bay and load a stock rocket, I've chosen Kerbal X. (Open -> Kerbal X -> Load). This one is great for getting far into space, and easily can hit Mun's orbit with fuel to spare. FIRST THOUGH, we need to change two things. Select the Engines tab and choose the 24-77 "Twitch" Liquid Fueled Engine. Push the Symmetry button in the bottom-left to get two of them opposing eachother, and stick them on the nose cone somewhere. They will be fine.

Next, under Fuel Tanks, select a Round-8 Torodial Fuel Tank. Place this BETWEEN the parachute and the nose cone. This will allow you to use the engines you've added to land, without them or their fuel being decoupled along this rocket's staging.

Launch time. After throttling up to full, ignite, release supports, and watch it go up. Two engines will run out of fuel and need to be decoupled AFTER they run out. Do this for each pair as they run out of fuel, throttling full the entire way. Eventually you will even need to decouple the biggest rocket and push a little harder with the last big engine.

Notes: You can combine stages 7 & 8 if you like, or push A a second time after igniting the engines to release the rocket.
SAS control on will be a lifesaver for you throughout launch. Keep in mind that it will use up all your electricity if you wobble around in space, but engines will recharge it.

By this point you should be viewing space view ( and ) and checking how far out your rocket is. At around 100,000M, you can slow down the throttle as you have many minutes before catastrophic failure so you can fart around with the controls to get this right. aim your reticle on the NAVBALL until its in the purple circle, and throttle up until your ship's trajectory intersects the Mun's. This is where it gets tricky. You need to time your spaceship arrival with the moon's pass, which may involve a LOT of luck. The easiest way to get lined up with the moon is by getting into orbit which can be very difficult to nail it on your first pass (or return-pass).

The method I used was by creating a massive orbit around Kerbin that also passed through the Mun's orbit (2x, once going out once going in) and speeding time up until my orbit got close to intersecting the actual Mun. Eventually you get close enough that you can burn some fuel to get your trajectory closer and closer to the Mun's so eventually gravity steals your momentum and you get sucked into Mun orbit. From here you need to use your thrusters (this time aiming at the YELLOW CIRCLE WITH AN X and this will slow you down. use your own judgement for how much fuel you have left VS the speed you need to decelerate, and hopefully you can get your craft to plop down on the moon softly. The engines at the end DO NOT HAVE MUCH FUEL so be weary when using this at the very end of your journey, as it is the worst place to mess up. ( THOUGH SAVING IS USEFUL ).

Note: The parachute will not deploy on the mun. I just left it on the craft because I don't want to fiddle with what already works :).

For the actual achievement to pop, hover over your crew members and push B -> EVA, and that should be the bleep bloop. Congratz! Now you just have to get there, AND RETURN. EZ, right?