If the system is to boot into X by default, Open `/etc/inittab` as root, change the following line:
{{{
# Default runlevel. (Do not set to 0 or 6)
id:3:initdefault:
}}}
To this:
{{{
# Default runlevel. (Do not set to 0 or 6)
id:4:initdefault:
}}}
This sets your default run-level to 4, which is Slackware's "graphics-only" mode (with one extra tty open, just in case, on vty6). Save, and on your next reboot, the system will boot into a nice graphical login.
You can manually enter run-level 4 by entering, as root, `init 4`
To select or switch between available desktop environments, run `xwmconfig` as root (`wmconfig` from CLI)