First of all you must install this plugin. To do this you must have working version of WordPress. If you dont have installed version, than read the WordPress codex - http://codex.wordpress.org/Installing_WordPress
Plugin installation can be done within two ways:
1. Installation via FTP
- Download plugin file and unzip it.
- In the extracted folder you will find 'share-this-image.zip' file. Extract it .
- Upload 'share-this-image' folder into Plugins folder in your WordPress installation (/wp-content/plugins) using an FTP client.
- Log into your WordPress admin panel and click on the “Plugins” tab.
- Find installed plugin from the list and click “Activate” button.
2. Installing From WordPress Dashboard
- Download plugin file and unzip it.
- Log into your WordPress admin panel and click on the “Plugins” tab.
- Navigate to Add New > Upload
- Click 'Choose File' and select share-this-image.zip file on your computer.
- Then hit “Install Now” and the plugin will be uploaded and installed.
- Than click “Activate” button.
Once the plugin is installed and activated you can set its major settings from plugin settings page.