1. Log in to your facebook account.
2. Go to your info and view your 'About Me' section.
3. Click on edit at the upper right of the section and change your birthday to the current date.
4. Save changes.
5. Enjoy all the wishes and see who's your true friend.
6. Repeat step 1 to 5 till nobody wishes you again.
This is an example of troll from the second day.
Reminder: Please be aware that some of your friend will eventually confuse and ignore to know your real birthday.