Place the moresuits folder in your BepInEx/Plugins folder.
You can add .png files to the moresuits folder to add new suits as long as both the host and clients have the same files.
You can add a .json file in the advanced folder with the same name as your .png file in the moresuits folder to enable additional features like emission. Place additional texture maps in the advanced folder.
Add a "PRICE" key to your advanced .json to put a suit in the store rotation.
Upload your own package with a BepInEx/plugins/moresuits folder in it (do not include the MoreSuits.dll file) and add x753-More_Suits-1.4.0 as a dependency, and this mod will automatically load your .png files as suits. If you don't want some or all of the suits that originally come with my mod, adjust the config file BepInEx\config\x753.More_Suits.cfg. Include a !less-suits.txt file in your moresuits folder to disable all the default suits that come with this mod.