This tutorial will explained how to install Ghost themes. It's very simple and easy, just upload your theme to:
cd /home/aris/ghost/content/themes wget https://codeload.github.com/durgesh-priyaranjan/magnum/zip/master -O magnum.zip wget https://codeload.github.com/Ghostrrr/ghost-theme-uikit/zip/master -O uikit.zip unzip uikit.zip unzip magnum.zip rm *.zip mv magnum-master magnum mv ghost-theme-uikit-master uikit
After that, restart your Ghost then login to Ghost Admin Panel. Go to Settings page and select the Themes you want to use.
That's all. So easy huh?