If you're after completing this achievement ASAP, open the spoiler. If you are after enjoying the story without spoiler, just continue playing as you would and this will eventually unlock.
Things might be a little different for you as choices affect how the story goes.
*** Spoiler - click to reveal ***
First prevent yourself from crashing, then finish the Iron Golem before placing the bucket of water down. Inside the tower, you'll get surrounded by the "Ocelots". Convince Lukas and choose your new armor to finish the episode.