Installer is so clear that don't need documentation, just boot the iso image and follow instructions. Check post installation actions.

Install vim, spectrwm, w3m?, git?, xsel? and xfe?;

# pkg_add vim spectrwm w3m git xsel xfe


Configure tmux.


After user does login on xenodm, Xsession script checks for a file named .xsession in the users home directory. Edit ~/.xsession to customize X, for example to use spectrwm window manager;

# use UTF-8 everywhere
export LANG=en_US.UTF-8

# specify location of kshrc
export ENV=$HOME/.kshrc

# load Xresources file
xrdb -merge $HOME/.Xresources

# set your background color
xsetroot -solid dimgray

# xidle will lock your display after a period of inactivity
xidle &

# sadly, xclock has a bug where the font selection is ignored when UTF-8
# is enabled, so we unset LANG here.
#LANG= xclock -strftime "%a %e %b %Y %H:%M" &

# disable system beep
xset b off

# if you have a ThinkPad, the following lines enable TrackPoint
# scrolling by dragging with the middle button.
xinput set-prop "/dev/wsmouse" "WS Pointer Wheel Emulation" 1
xinput set-prop "/dev/wsmouse" "WS Pointer Wheel Emulation Button" 2
xinput set-prop "/dev/wsmouse" "WS Pointer Wheel Emulation Axes" 6 7 4 5

# use caps lock as ctrl key
setxkbmap -option ctrl:nocaps

# start spectrwm!
exec spectrwm

SSH keys are handled on /etc/X11/xenodm/Xsession. To change resolution of X xenodm edit file /etc/X11/xenodm/Xsetup_0 and add at start;

xrandr --output HDMI-1 --mode 1920x1080

Stop/start xenodm (X / session manager), check customizing xenodm;

# rcctl stop xenodm
# rcctl enable xenodm
# rcctl start xenodm

Spectrwm example configurations are at /usr/local/share/examples/spectrwm/.

On Firefox type about:config in the address bar. Search for ui.allow_platform_file_picker. Toggle it to true.