#Install LXDE:

pacman -S openbox lxde gamin dbus   #Lxde and needed dependancies
pacman -S xorg-server xorg-xinit xorg-server-utils   #Xorg
pacman -S mesa xf86-video-fbdev xf86-video-vesa   #Video Drivers
#To use startx, you will need to define LXDE in your ~/.xinitrc file:
echo “exec ck-launch-session startlxde” >> ~/.xinitrc

autologin & autostart LXDE

cp /usr/lib/systemd/system/getty@.service /etc/systemd/system/autologin@.service

Then in /etc/systemd/system/autologin@.service add your login insted of USER:

ExecStart=-/sbin/agetty --noclear -a USER %I 38400

Then:

# systemctl daemon-reload
# systemctl disable getty@tty1
# systemctl enable autologin@tty1
# systemctl start autologin@tty1

Then:

cp /etc/skel/.bash_profile ~/.bash_profile

And then in this file add:

[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && exec startx