In this instructable, I will show you how how fancy your Ubuntu (or other linux distribution)

In the screenshots I used Ubuntu 17.10 with desktop enviroment Gnome.

Step 1: Step 1: Install Gnome Tweak Tool

You can use Gnome Tweak Tool to set your theme and icon theme. So the first step is to install Gnome Tweak Tool. To install, open the terminal and type:

sudo apt-get install gnome-tweak-tool

Then press enter. A password is asked, so type your password and press enter again. The installer will ask if you want install gnome-tweak-tool, so press "y" to continue.

Step 2: Step 2: Install a Modern GTK Theme

There are several GTK themes aviable to fancy your ubuntu desktop:

Arc Theme

sudo apt-get install arc-theme

Enter your password again and press "y" if asked if you want to continue.

Numix Theme

To install the Numix theme you first have to add the repositories to get Numix packages. Fire up a Terminal and run the following:

sudo add-apt-repository ppa:numix/ppa

sudo apt-get update

After this its possible to install the Numix GTK theme:

sudo apt-get install numix-gtk-theme

After you have installed the theme you want, you have to set the theme.

Open the application menu and open Gnome Tweak Tool

In the tab Apperance > Themes > Applications, you can choose the application theme.

Step 3: Step 3: Install a Icon Theme

There are several GTK themes aviable to fancy your ubuntu desktop:

Papirus Icon Theme

sudo add-apt-repository ppa:papirus/papirus

sudo apt-get update

sudo apt-get install papirus-icon-theme

Enter your password again and press "y" if asked if you want to continue.

Numix Theme

sudo apt-get install numix-icon-theme-circle

After you have installed the theme you want, you have to set the theme. Open the application menu and open Gnome Tweak Tool In the tab Apperance > Themes > Applicatoins you can choose the application theme.