Windows 7: How to Upgrade from Windows 7 Home Premium to Windows 7 Professional

I have a new laptop that came with Windows 7 Home Premium. I bought Windows 7 Professional Upgrade from download and the backup disc. Please point me to the appropriate installation instructions for this scenario. Need and appreciate help

Addendum: Unfortunately, the Windows 7 Professional Upgrade I purchased is not the Anytime Upgrade and it can't be returned since it was obtained through the student program. So do I need to reformat this hard drive and install my upgrade version from boot?? If so, how is the reformat accomplished?

Press windows and pause/break keys together.

In the new window that pops up, select change product key.

Put your new Professional key in.

Then Activate.

Retail Upgrade and Full keys will work for Anytime Upgrade.

Type "Anytime Upgrade" in Start Search box, insert Professional Product Key at prompt. In about 15 minutes the extra features for Pro will be unlocked while all of your programs, files and settings are kept in place.

If you would rather get rid of the factory bloatware and useless utilities which have better versions built into Windows 7, here are steps for Reinstalling Windows 7

No install files needed.
Only the Upgrade key is neeed.
Anytime upgrade only adds-on the Programs & Features from version to version.
Windows Anytime Upgrade - How to