Today I came across another one called Pinterest Hover Pin It Button. I tried installing it and it works perfectly. And it is very easy to set it up.
1. Go to: http://wordpress.org/support/view/plugin-reviews/pinterest-hover-pin-it-button
2. Click the orange color Download button. It is in .rar file.
3. Now go over to your WordPress Dashboard.
4. Select Plugins >> Add New.
5. Click Upload.
6. Click Browse. A box will pop up.
7. Look for the downloaded file as shown below:
8. Click on it. Then click Open.
9. Now click "Install Now" button.
10. Next go "Settings" and look for "Pin It Button". Click on it.
11. It will take you to a page called "Pin It Button Settings".
12. Click on the small box (tick) next to "Enable the Pin It hover button over images".
13. Make the other setting options to your preference. (language, size and color)
14. Finally click the blue color "Save Changes" button.
That's all.