Login to your facebook account.
Go to Account > Account Settings.
Here you can see “Download your information”.Click “learn more” option.
After Click “learn more” option,you will receive a warning message that keep your data and information after downloading it.
Click the Download button.
Once you click the “Download link”,just wait sometime for your email with a download link.It will take near to 1 hour.
Check your Inbox.You will receive an email
Click the link,it will prompt you to verify your password before you download the file.