Most important lesson you've learned in KSP?

[Kerbocracy]

If conduct test-launches using autonomous control (e.g no Kerbal pilot), make sure you clear the Kerbals out of the command seats during every launch from the VAB as they will be automatically populated there each time you edit the craft. How many times have I changed a single strut, done a launch, and at 13km in the air with a wonky launch, realize Bill is in the pod and there is no safe way home...

If you are launching docked components, remember to 'Disable Crossfeed' unless you want to burn fuel from the component you are launching.

When placing ladders, check to make sure it didn't automatically apply the symmetry mode of the underlying stack. When is it appropriate to have a ladder on every side of the craft? I often don't realize this 'bug' until I'm in orbit.

[boolybooly]

Never believe dV calculators... always try it for yourself

[Roman_legion]

They will if they're equidistant from the CoM...

While that is true, it is rarely the case for most things you want to dock that they have their CoM in the EXACT middle of your craft.

Also, when docking, orientiate yourself using the nav-ball, having kerbin either to your left or to your right. That is the direction in which the 'ground' part of the navball will be oriented.

[Pipcard]

Never believe dV calculators... always try it for yourself

Maybe, if you're talking about jet aircraft, or SSTOs with jets and rockets.

But not for pure rockets.

Just leave an extra few hundred meters per second of delta-V, just in case.

Edited October 30, 2013 by Pipcard

[psistorm]

When trying to land on Duna, for heavens sake bring either an engine for powered descent, or do what I did and set a really shallow orbit so you can aerobrake. Don't do what I did before and try and enter like kerbin, since then you will come in hot and fast and when the chutes deploy, your craft will be torn up by slowing down from supersonic to 10m/sec in a split second.

When trying to land on Eve, bring enough torque to keep your craft facing retrograde or make sure the drag is balanced correctly. My probe decided to face nose down no matter what for lack of torque, and the further you come down, the more impossible it is to turn the vessel again.

After assembling your rocket, press Q once while holding the origin piece, that way you will be facing at 90° and can do a gravity turn by pushing downward. I always found that easier.

On planes, balance your control surfaces. Use the appropriate size for your vessel, and don't put them too far away from the CoM, else you will have a very twitchy craft

[Tassyr]

Here's one I JUST learned. If you're going to crash due to lack of fuel, aim the 'unimportant' end (Legs, batteries, engines, anything without a pod) directly at the ground. Surprisingly I had kerbals survive a 67m/s impact this way.

Admittedly there's JUST a pod left on the mun, but. Beside the point.

(Related: Polar landings take a LOT more delta-v.)

Edited October 31, 2013 by Tassyr

[kelmv]

When trying to stop a runaway rover, it is rather hard to 'dock' your kerbil into the flight seat. It seems they have trouble flying, landing, sitting, and stopping an out of control rover all at once.

[Melonfish]

Jeb is clearly a clone, or he's captain scarlett in disguise. i've splattered that little guy across the surface of at least two moons and most of kerbin and he still ends up back in the flippin capsule!

[Knobby]

I learned that I have to watch a Scott Manley video before trying out new stuff, saves me a lot of time and Kerbals!

Edited November 1, 2013 by Knobby

[WafflesToo]

Maybe, if you're talking about jet aircraft, or SSTOs with jets and rockets.

But not for pure rockets.

Just leave an extra few hundred meters per second of delta-V, just in case.

Two words, "docked landers". Been burned too many times on that one to blindly trust an automaton.

[tanuki_chau]

I learned to trust my instincts in regards to orbital trajectories. Just close my eyes, visualize, and execute.

[PrivateFlip]

Let's say you want to travel to Duna. If you do the complete transfer burn in low earth orbit, instead of first escaping Kerbin and then doing the actual transfer burn while in an orbit around the sun, you'll save a ton of fuel. (It's true)

[Aladran]

Don't go to a journey without static solar panels, what worst than not being able to deploy your big solar power because there is no more juice in the batteries...

[Flymetothemun]

Humanity is damn small and that space is beautiful. This game makes me think about my existence.

[djnattyd]

It's really, really, really easy to get dislodged from the surface of Gilly. Remember this before trying to walk down a hill.

[spudcosmic]

Save as much weight as possible.

There's no need to add a bunch of fuel and nuclear engines if you can get the job done with a much smaller craft.

[zxczxczbfg]

When you're trying to send up a space station, make sure the crew are on board before you launch.

[Mirimus]

Don't kick the baby!

[Tobbzzzz]

Never ever disconnect your lifter when it's fuel left and the engines are on...

[Wampa842]

Always reserve a little fuel to get home in case shit hits the fan.

[Daystrom]

When everything is going well, you have forgotten something.

For example, if you land on the Mun using the tried and tested Lunar Orbit Rendezvous method, try to remember that the ship that is taking you back to Kerbin is orbiting in exactly the wrong direction to the direction you would normally launch.

[GamerMitch]

I kept forgetting to add an SAS module when I first started,so I remember to do that now.Also,I remember to add Ladders when I go to the moon.

BIGGEST THING:It may look like you have enough fuel, but it will come back and bite you like when I only got to Eve orbit with a LANDER.THAT SUCKED.

[spyker92]

If at first you don't succeed, add more boosters.

Explosions are dangerous. And friendly. And like to come over for tea.

[Beachernaut]

That bit of text that flashed on your screen is important.

It said "Cannot quick save while throttled up"

[Kronuxen]

K.I.S.S

Keep.it.simple.stupid

Best lesson I learned on creating stuff XD