How to remember birthdays
It made me
Organised 
"You don't need to have a good memory in order to remember birthdays and special events. All you need is a pen and a small book."
How I did it: I used to use BirthdayAlarm.com to keep a note of birthdays. Now, I simply write them down at the back of my address book.
Another good idea is to store them on your email account's calendar.
