A more detailed illustrate in Archwiki:
According to Archwiki the
no longer actively updated, so the better choice is using
libinput as touchpad driver. run:
# pacman -S xf86-input-libinput
the config file of
libinput is located at
/etc/X11/xorg.conf.d/. create a new file named
the location path, and write a new section labeled “InputClass” in it in such format:
Section "InputClass" Identifier "libinput touchpad catchall" MatchIsTouchpad "on" Driver "libinput" EndSection
libinput for touchpad supports clicking and srcolling. to enable tap-as-click
you need to add in the section body:
Option "Tapping" "on"
natural scrolling permits you scrolling in a reversed way. add:
Option "NartualScrolling" "true"
for more options see the man page