Adding admins

1. Make sure you stop your 7 Days to Die server
2. Click on Files
2. Click on the following folders local_data > Saves
3. You should now see a file called serveradmin.xml, double click on this file to open it.
4. Once the file opens scroll down until you see the following lines:

<admins>
    <!-- <user steamID="76561198021925107" name="Hint on who this user is" permission_level="0" /> -->
    <!-- <group steamID="103582791434672565" name="Steam Universe" permission_level_default="1000" permission_level_mod="0" /> -->
</admins>

5. Now add the following line below the line that starts with <group

<user steamID="SteamIDHere" name="SteamUserNameHere" permission_level="0" />

Replace the SteamIDHere with the Steam64ID of the player you wish to grant admin to and also replace SteamUserNameHere with the Steam username of the player so you can identify the admin easier.
You can find the Steam64ID of the player by following the guide over at https://www.creeperhost.net/wiki/books/steam/page/how-to-find-a-players-steamid

6. It should now look something like

<admins>
    <!-- <user steamID="76561198021925107" name="Hint on who this user is" permission_level="0" /> -->
    <!-- <group steamID="103582791434672565" name="Steam Universe" permission_level_default="1000" permission_level_mod="0" /> -->
  <user steamID="SteamIDHere" name="SteamUserNameHere" permission_level="0" />
</admins>

7. Click on save then start your server up again.