Download the "example 2" mod pinned at the top of the forum. Replace all the"red tempest" data with your own including the ex2_mission1.java stuff.
Took me a few hours for my first time modding anything. just make sure you spell everything right, and when the game crashes check the "starfarer-core">"starfarer log.txt" to find out why
Piece of cake.
Sorta