The Guide shows you the Steps for Switching from Lxde to GNOME3 Desktop on Debian Linux Wheezy.
To Login into the Lxde Desktop we will just Make Use of the slim Display Manager, the Default Debian Lxde Display Manager.
Finally, the post’s Content is Expressly Reduced to Give Focus to the Essentials Instructions and Commands.

-
Installing the GNOME3 Desktop.
Copysu
If Got “User is Not in Sudoers file” then see: How to Enable sudo
Copyapt-get install aptitude tasksel
Copytasksel install gnome-desktop --new-install
-
Installing and Switching to Slim Display Manager.
Copyaptitude install slim
Choose the slim Display Manager.
-
Disabling the gdm3 Display Manager.
Copyaptitude install rcconf
Copyrcconf
Disable the gdm3 Display Manager.
-
Here Setup Slim for Running a Desktop on Debian:
Debian Slim Setup How-toTutorial on How to Setup the Slim Display Manager for Running a Desktop on Debian Linux. -
SetUp GNOME3 for Starting at Boot.
Copysu <username>
Copynano ~/.xinitrc
Inserts:
Copyexec gnome-session
-
Rebooting into the Debian GNOME3 Desktop :)
Copyreboot
How to Install Google-Chrome Web Browser on Debian:
How to Easy Download and Install Debian Unstable Sid: