There are 2 ways to change your icon.
Access My Settings.
1. You can change your profile picture by clicking the "upload file" button.
You can choose any picture from your computer.
2. If you have linked your Facebook or Twitter, you can simply change your profile picture by clicking the "select" button. Then your profile picture will be the same as your Facebook or Twitter account's.
* Facebook and Twitter will be linked after your account has been verified.