1. Launch QuickTime Player
2. From the QuickTime Player menu bar click on QuickTime Player
3. Then click on Buy QuickTime Pro

You must have an active connection to the Internet because a browser will then launch and take you directly to the Apple Store.  From there you complete the steps to purchase QuickTime Pro.

Apple will then provide to you a QuickTime Pro registration code via email.  Once you obtain the code, you will have to enter the code via System Preferences to complete the upgrade.

1. System Preferences
Launch System Preferences
Then click the QuickTime Icon.  The Registerbutton is highlighted by default.

2. Enter
In the "Registered To" and "Registration Code" boxes enter your name and registration code exactly as they appear in the email sent to you by Apple.  Note that the "Organization" box is optional, you don't need to provide information for this field.

3. Check
The easiest way to determine if QuickTime Player has been upgraded is to QuickTime Pro is launch the application.