Minmus 101: Landing on Minmus and coming back
Minmus is probably the first place you want to go to, due to its low gravity, flat landing areas, and relatively low orbital inclination. It was the first place I ever sent a rocket to.
There is no one perfect vehicle for going to Minmus because all players have different preferences. With that said, I have a design that is capable of going to Minmus and back with some piloting skill.
Enter the Vehicle Assembly Building. You will need a command pod, preferably an Mk1 Command Pod due to its low weight and good aerodynamics, a Mk16 Parachute for coming back to Kerbin, and if you are playing in Career or Science mode, some science experiments (ex. Mystery Goo, 2HOT Thermometer, PresMat Barometer, etc.). You lastly will need a heatshield, though this is not required as long as you have control fins such as the AV-T1 Winglet. This can be your return module, but can be upgraded with another Mk1 command pod if you want to carry 2 kerbals. You may put more, but do it as your own risk as I do not know if it can be carried with the lander stage. If you are planning on also taking a lone scientist, you may want a Probodobodyne OKTO, so you have some SAS capabillities.
The lander stage is comprised of a TD-12 decoupler, a FL-T200, a FL-T400, and a LV-909 "Terrier" engine. LT-05 Micro Landing Strut landing legs are optional, but recommended to avoid tipping over. Put 3 or 4 of the landing legs.
Next, your core stage, will comprise of 4 FLT-400's, and a LV-T45 "Swivel" Liquid Fuel engine. Near the bottom place 4 Basic Fins for stability (optional). If you are using other fins on your capsule, keep putting more basic fins until you manage to bring the Center Of Lift below the Center Of Mass.
Lastly, your boosters, are attached by 2 TT-38K radial decouplers, and are made of 3 FLT-400's, with some kind of lightweight nose cone on top. The boosters will be powered by 2 LV-T30 "Reliant" Liquid Fuel engine. If you have unlocked it, you may want to place fuel lines from the boosters to the core stage for more efficiency. This is not required but will make your flight much easier. Before launch make sure you have your staging set correctly; at the bottom it should have the boosters and core stage, then above it the TT-38K radial decouplers, then the TD-12 decoupler, the LV-909 "Terrier", the topmost TD-12 decoupler, and the parachute at the very top. A final addition, add parachutes if reusability is desired, and place the parachutes in the stage where they are seperated off. This allows recovery without more OKTO's.
First, ignite the boosters and the core stage. Press the "D" key once to begin your gravity turn. Wait until you have reached 2 km, and then hit "D" again. When you have reached 5 km hit "D" once more and keep flying. If you begin turning out of control, use the WASDQE keys to stabilize. When your boosters are out of fuel, hit "SPACEBAR". You will notice that your core stage is still filled with fuel. This is what the fuel lines were for. Now fly to a 70-80 km orbit, and if you do not know how to do this, first practice getting to orbit by using a tutorial on how to get to orbit. Once you are in orbit, zoom out on map view. Look for a purplish dot with an orbit that circles Kerbin. This is Minmus, and click on it. Click "Set as Target". If you do not see it pop up, either click the other side of your touchpad/mouse, and if that doesn't work, upgrade mission control. Once you set Minmus as target, your orbit will have a decending node, and an acending node. Plan a maneuver node and pull on prograde until you get an encounter with Minmus. Click on Minmus and select "Focus view". If you have gotten an encounter, you will see a marker that says "Minmus Periapsis". Timewarp to an area in your orbit until you are at T-15 Seconds till you reach the node, point towards the Maneuver marker (the one with the dot and 3 lines that is blue), and hit "Z". If you want to speed up the burn, timewarp while pressing "Alt" (on windows). Once you are getting close to finishing your burn, hit "X" and "SHIFT" until your periapsis is close to your planned one. Hit the X on the maneuver node on the side yellow bar. Plan another maneuver node at Kerbin Apoapsis, and use the Anti-Normal/Normal, Radial In/Out, and Prograde/Retrograde on this one. Correct your inclination, adjust your periapsis to the right height. I prefer 10 km because it isn't scarily low, while being low enough to land easily and come down at low speeds. Once you enter Minmus's SOI, you may want to do science experiments if it helps. Plan a maneuver node again to capture into Minmus orbit. Remember to pull on the retrograde marker this time. Once approaching Minmus, begin burning until you are in a stable orbit. Make sure your apoapsis and periapsis are within at least 5 km of height. You may want to use a Minmus biome map to select your landing spot. For this tutorial we will land on the Greater Flats, so you have a large area to take off, and it is flat. When you see that you are almost directly above your landing site, burn full throttle, and completely bleed off all your horizontal velocity. Fall down to 2km, and burn straight up until your speed is below 20 m/s and cut. Burn at low throttle, open your landing gear, and slowly come down until you come near the ground, at which you slow your speed to >3m/s. Congratulations, you have landed on Minmus!
Do your science experiments,if you have DLC installed take a Green Sandstone sample, plant a flag, jump as high as you can, and simply look out at the wonderful view! Once you are done with this, your crew may no longer wish to stay on Minmus, and may want to go back home to Kerbin. To takeoff, you will want to ignite low throttle, and point west to reach orbit. Once you have reached orbit, you want to make sure that you have enough fuel to transfer back to Kerbin, which should be around 300 m/s, 400 m/s to be safe. If not, leave your crew in orbit, and somehow send another rocket and bring them back. If you have enough fuel, wait until you see Kerbin directly away from Minmus. Fire full throttle until your "Kerbin Periapsis" is 40-50 km. Once near Kerbin, make sure you have taken all your data into the capsule, and re-enter. Keep aerobraking, and then if you want, you can try and land near the KSC for maximum funds in career mode. Now that you have landed on Minmus, what's next? Maybe landing on the Mun?