Simple step to install a desktop (Gnome) on Solaris 11
As root run the following command
# pkg install solaris-desktop
If the download of the packages and installation is successfull you would see an output similar to below
Packages to install: 370
Create boot environment: No
Create backup boot environment: Yes
Services to change: 14
DOWNLOAD PKGS FILES XFER (MB) SPEED
library/gnome/gvfs 147/370 33288/53216 277.9/547.3 -92191B
...
PHASE ITEMS
Installing new actions 84196/85615
...
Installing new actions 85615/85615
Updating package state database Done
Updating image state Done
Creating fast lookup database Done
Reboot the system and you will now be presented with the desktop login dialog