With the Atlas Rises Update we've gained an in-game Wiki which is used by the vanilla game to show helpful information to the player. However, this is a perfect place to give players information about our mods and how they can best be used.
This guide will show you how to edit the Wiki pages to include your information and establish some base guidelines on how to add info so players can find mod information in the same places consistently.
The file you will want to modify is /METADATA/REALITY/WIKI.MBIN.
Once you decompile it and open up the exml file You'll want to navigate to the 5th GcWikiCategory section which is for New Features in Vanilla. I changed it to New Features and Mods.
Now you'll want to copy and paste the last GcWikiTopic section in that category and use it for your mod.Change the Topic ID to your mod name, add a reference to your custom mod icon if you made one (if you didn't just pick a vanilla DDS icon that fits).
Now you'll want to move down into the Pages section (NOTE: You can make multiple pages and it will work except the player won't be able to access anything but your first page as HG did not implement a 'Next Page' button).
The PageID will basically be your mod name again and the Content section is where you're going to put the majority of your text.
A couple things you'll want to know regarding Content. First of all, if you're putting a decent amount of text here (which you probably are) you'll need to actually put it into the LANGUAGE file and just reference it from Content the way it's done in Vanilla. But if you have (I'm guessing) less that 256 characters you may be able to cram it in here


 is line break. You'll want to put it at the end of your paragraphs.
<TECHNOLOGY>Base Teleporter<> is the format to high-light things a different color. You can replace TECHNOLOGY with other types and it will alter the color.
You can also reference keyboard shortcuts that will auto-update based on the players control config (keyboard, controller, etc). <IMG>CYCLEWEAPON<> would reference the button the player needs to push to cycle their weapons.