What was the first thing you did when you bought KSP?

[lllmaxlvllll]

Built a simple rocket , made sure everything lined up just right , checked to make sure it was balanced , put it on the launch pad , and realized that the stages were mixed up when I tried launching but only deployed my parachute.

[GRS]

Build some random stuff and Launch them, after getting a fairly large rocket, i kept groaning for no reason, turns out...

Spoiler

I [REDACTED] FORGET TO USE "SAS" !!!

As i Launch it properly, it effortlessly gained orbit, and Get to Mun, but crashed thanks to inabillity to terminate speed before Touchdown...

[l0kki]

I built a mig-15 replica that looked nothing like the mig-15 which could reach 1600m/s at roughly sea level

[A Random Kerbonaut]

The first thing I did, I made a career mode, 

didn't know how to turn on liquid fuel engines,

got bankrupt,

switched to science mode, 

then I did some tutorials and did sandbox.

I know know a few things about orbital maneuvers now,

I play normal career and sandbox now.

 

[Dan Kerman]

Went thru the tutorials to learn the basics game functions...  then here to learn more and start career mode.