added info on first boot and opening the settings app

docs/linux/debian12_config.rst

@@ -3,12 +3,31 @@ Debian 12 post-install configuration
 
 Please remember these are my own preferences so you should accept or refuse based on your own needs.
 
+First boot
+----------
+
+Select your user account and login. I know this seems obvious, but I've met so many people who have only ever used Windows with autologin set.
+
+Once logged in the first thing you should see is the Debian ``Welcome`` app. I recommend skipping each screen of this as I've found that changing things at this point can leave the System unstable. Anything that matters will be covered in the next section.
+
 Settings
 --------
 
+There are four ways to open the settings app that I'm aware of:
+
+- press the ``Super`` key (most likely the ``Windows Start`` key) and start typing "settings". After just a keystroke or two you should see it in the list.
+- press the ``Super`` key and on the bottom taskbar that appears, click the icon with 9 dots (3 rows of 3). This will show the installed applications and you should be able to spot and launch the settings app from here.
+- right click on the desktop and select ``Settings`` from the popup menu.
+- click the top right of the screen, where the network and volume icons should be, and on the drop down menu click the little cog wheel icon.
+
+In order to keep this part succint I will use the following format to indicate which tab, sub-tab, option and setting to apply. The number of items in the chain will therefore vary depending on the structure of the options available:
+tab -> sub-tab -> option -> setting
+
+Appearance -> Dark
 
 Tweaks
 ------
+
 This option is necessary if you use a laptop with an external monitor. On the ``General`` tab toggle ``Suspend when laptop lid is closed`` to ``Off``.
 
 On the ``Appearance`` tab set ``Legacy Applications`` to ``Adwaita-dark``.