Debian 8 Jessie comes with a dull icon theme. I think I need something fresh and better icon theme for my Jessie. Numix Icon Theme could be a good start. Install Numix Icon Theme on Debian 8 Jessie is pretty easy. There are many Numix icon theme variations. And the one that looks great is the Numix Icon Theme Circle.
Because Numix Icon Theme Circle is available through github, first we need to install git on Debian 8 Jessie. Do these commands below as root privilege.
apt-get install git
Download or clone Numix Icon Theme Circle
git clone https://github.com/numixproject/numix-icon-theme-circle.git
mv Numix-Circle /usr/share/icons
mv Numix-Circle-Light /usr/share/icons
Now apply the icons using Gnome Tweak Tool. Install it if you don’t have it yet
apt-get install gnome-tweak-tool