How To Add Modlets To A 7 Days To Die Server
First we'll cover what a modlet is. 7 days to die has a number of ways to mod it. We have what we dub hard mods, then we have then modlet system. Hard mods are a little bit more tricky to get working, and can make big changes to the game. A modlet allows modded to make changes to the xml files no direct changes are mod to the files. This allows for easy installation and removal of modlets and also means less conflicts between mods. Modlets can also be removed from your server without needing to reset your world, or other files.
Finding Modlets
First, we need to find a modlets to install. The best location for this will be on the 7 Days To Die forums. 7 Days To Die Forums You can also find modlets on the Nexus Mods website.
When using the forums make sure to check for mods marked with the modlets tag. As we said before, there are other kinds of modding in 7 Days To Die, and we want to make sure we are getting a modlet.
Every modlet when downloaded will have a modinfo.xml inside it. Check to make sure this is here. If it isn't you might not have a modlet.
Installing Modlets On A Client
Head to steam, then right click on the game in your library and select properties.

This should open a new window, we're then looking for the browse button. This will take you to the files for 7 Days To Die.

Here we'll make a folder called Mods, and put all the modlets we want to load.
If you would like a guide on how to install a modlet on your server, please see here Installing modlets on the client
Removing Modlets
Removing modlets from the server is a simple as removing the file from the folder and rebooting the server.