"Steps to follow"
1. Select the websites you want to block in the "Select Websites to Block" section.
2. If you want to block any website other than the specified websites, then enter the name of the website or the url of the website. The domain name to be blocked will be automatically detected.
3. After selecting the websites click "Click and Download File" button; --after waiting for 3 seconds a .zip file will be downloaded--
4. Unzip the file at any location in your PC.
5. Now go to "Manage Extensions" of chrome and select "Load Unpacked" at top left corner of the page.
6. Now navigate to the zipped file and select it.
7. Switch on the extension and Bien joué! It's done.