1: create the category in "addons/darkrpmodification/lua/darkrp_customthings/categories.lua" by putting that in there and changing the values to your liking
Code:
DarkRP.createCategory{
name = "Citizens", -- The name of the category.
categorises = "jobs", -- What it categorises. MUST be one of "jobs", "entities", "shipments", "weapons", "vehicles", "ammo".
startExpanded = true, -- Whether the category is expanded when you open the F4 menu.
color = Color(0, 107, 0, 255), -- The color of the category header.
canSee = function(ply) return true end, -- OPTIONAL: whether the player can see this category AND EVERYTHING IN IT.
sortOrder = 100, -- OPTIONAL: With this you can decide where your category is. Low numbers to put it on top, high numbers to put it on the bottom. It's 100 by default.
}2: Then you want to change the job's category by adding the following line into the code (replace "category_name" with the name of the category you created, once a category is made you can use it in as many jobs as you want)
Code:
category = "category_name",