You can't out of box.. this tutorial is one of 2 pieces.. originally linked in the topic is Stskeeps website which has the step by step on how to install NIT-Debian (although right this second it isn't step by step, as of last night there were installer bugs).. after NIT-Debian is installed you follow the steps in the OP to provide yourself with Gnome.

There's not a "Debian with Gnome" pre-package built yet.. you can use Debian Beta3 as a base if you want it now.. but beta3 is missing some important stuff; IE xmodmap for the N810 for the function keys; older wireless driver, no dimming/blanking of the screen.. but overall beta3 was a good starting point.

However you get a bootable debian on your tablet the OP tells you how to put gnome onto it..