WordPress.org

1. Extract the zipped file and upload the folder html-javascript-adder to to /wp-content/plugins/ directory.
2. Activate the plugin through the 'Plugins' menu in WordPress.
3. Go to the Widgets settings page.
4. Drag the "HTML Javascript Adder" from the "Available widgets" to your sidebar.
5. That's all.

Usage

1. Just add a widget.
2. Enter the title and required content.
3. Check the boxes present below to show/hide the widget in specific pages.
4. Click save.

For usage, just see the screenshots. For detail usage and to use some inbuilt functions and features refer the Documentation page in Aakash Web