The two ways include:

Using PPAs and packages to install the theme and icons.Manually installing themes on your system.

​Installing Elementary Tweaks

​Before installing using PPAs, you might want to run the following in the terminal if you have never installed anything via PPAs(It is apparently disabled by the creators of elementary os) – Install Software Common Properties In Elementary OS

sudo apt install software-properties-common

​You will need to install Elementary Tweaks so as to change theme settings and icons. Open the terminal and type the following command – Install Elementary Tweaks

sudo add-apt-repository ppa:philip.scott/elementary-tweaks

sudo apt-get update

sudo apt-get install elementary-tweaks

Adding the required PPA Updating the system You might need to reboot to see the elementary OS tweaks tool in the system settings. After rebooting, you should see ‘tweaks’ in the system settings under personal. Accessing system settings in the applications menu in the top left corner. Tweaks option under personal in the system’s settings. The tweaks settings panel.​You will be able to change the Theme and the icons using the tweaks panel as shown here. Changing the GTK+ and Icons in the theme settings

​Using PPAs and Packages to install the theme and icons

​Installing of themes this way is as easy as installing any software on Ubuntu. Some themes come in the form of .deb files that are very easy to install. Download the .deb files then right-click the folder where the .deb file is located then choose open in then choose Terminal.​When the terminal opens up, type the following command to install the icons and the themes that you have downloaded – Install Theme In Elementary OS

sudo dpkg -i package-name.dpkg

​In my case it is – Install Themes In Elemtary OS From .deb file​

sudo dpkg -i paper-gtk-theme_2.1+r265_daily_ubuntu16.04.1_all.deb

sudo dpkg -i paper-icon-theme_1.4+r692_daily_ubuntu16.04.1_all.deb

The above is the paper theme and the paper icons. Installing themes using .deb files​After installing the .deb file, you can change the theme using the tweaks panel in settings as shown for both icons and themes. ​You can see the difference before and after changing the icons:

​Manually installing themes on your system

You can optionally install themes manually. To do this, you will need to create two hidden folders in our home folder, one for icons and another for themes.​You can do this in the terminal by typing the following command or ignore this step if you already have both these hidden folders in home directory – Create hidden themes and icons directory

mkdir ~/.icons && mkdir ~/.themes

​To view the created folders, you can type this in the terminal:​ You should see the .icons and the .themes folder.

cd ~

ls -a

Next, you will need to place the themes in the .themes folder and icons pack in the .icons folder.​But first, you will need to unhide the hidden folders as shown in the next section, after which you will place the themes in the .themes folder and the icons in the .icons folder. ​Alternatively, you can create the folder in the file manager. First, you will need to show hidden  folders by right-clicking the home folder and selecting show hidden folders: ​After which, right-click the same folder and select new then new folder. Rename the folder to ‘.icons’. Repeat the same for ‘.themes’ folder. Creating new folder Rename folder

Conclusion

​There are good themes out there you can try and tweak around with. They come in form of .deb files or .tar.gz files. Just extract the .tar.gz file into the icons or themes folders and you are good to go. The themes and icons will make your desktop experience look great and feel great. Don’t let some stock themes hold you back from getting the best out of your PC. But all in all, don’t forget to enjoy what themes you install, it will make your pc worth your while. Enjoy!