Getting to the dimension Edit
First, craft a Launch Pad with two titanium, a bucket of water, and three iron blocks
Place the launch pad in a 3x3 area.
Then, craft all rocket parts (Nose Cone, Body, Thruster, x2 fins) Some recipes may require copper and aluminum oxide crystal (found under Jungle biomes.)
This recipe requires copper.
Right-click the launch pad to open its crafting inventory. Place each rocket part in the following shape to craft the Horizon rocket.
Right-click the newly crafted horizon on the launch pad to place it.
Next, craft a rocket fuel to fuel the spacecraft. This recipe requires lithium and x2 uraninite.
Shift-right-click the rocket to open its inventory. Place the rocket fuel in the respective slot.
Then, right click the Horizon to enter it. Right click once more to engage the launch.
And there you go! Explore and have fun!
In order to get coral, you need to use a survival knife.