If you feel hard for getting themes for money, then this blog helps you to install pirated themes. But still it is not recommendable. Try to use original.
There are couple of steps to follow,
Install existing themes:
Go to wp-admin (www.yourWebsite.com/wp-admin) and click or hover mouse cursor on ‘Appearance’ which is in left side of the window, then select ‘Themes’ in it.
There are themes listed in selected window. If you ok with any one of those themes, then good. Click on ‘Activate’ link which is on bottom of each themes. Below image will give you clear picture of this context.
If you don’t like any one of this theme, then click on ‘Install Themes’ tab which is current window’s top second tab.
There, search with any related keywords which are very suitable to you. For example I’m searching with ‘blog’, It shows plenty of available themes.
There is install link available on each theme. Click on ‘Install Now’ link. It will take few seconds to install selected theme. Now theme will be downloaded from source url and placed under ‘yourProject/wp-content/themes/’.
Click ‘Activate’ link in current window if you want to set this is as your theme. Now enjoy with your new theme.
Install pirated theme:
If you have any themes in your hand, copy the theme folder and put/paste it in themes of your project root folder (‘yourProject/wp-content/themes/). Now come to first step. Click on ‘Appearance > Themes’.
Now the theme which you pasted in themes folder will be listed. Now click on ‘Activate’ link and enjoy with new theme.