How do I install Final cut on my notebook/external drive??

I Answered HERE and there wasn't really need for this thread as you asked the same question if the other thread but i will write again FCS2 is 52GB and you have 80GB HDD. Upgrade the HDD to max you can afford if you have an external drive transfer all important docs/videos/pictures as not to lose them when you upgrade. With you old HDD you can buy an HDD enclosure and have it as a back up

The good news is that the applications included with FCS2 only take up about 4gb of space. The remaining 62gb of "extras" can be installed on another drive. You'll be given the opportunity to do so during the install process. For more details, READ the "Installing Your Software" booklet that came packaged with FCS.

-DH

From Apple's FCS site:
Available Disk Space
• 4GB of disk space required to install all applications
• Additional 62GB required to install all optional templates, content, and tutorials (may be installed on separate disks):
- 9GB for DVD Studio Pro content
- 8GB for Motion templates and tutorial media
- 24GB for Soundtrack Pro audio content
- 12GB for LiveFonts and LiveType animated elements and templates
- 2GB for Apple Pro Training Final Cut Studio Tutorials media

Have you tried transferring everything on your mac to an External Drive and uninstalling programs so that you have 65GB (To be safe) then install FCS2 then move all the extras to External HDD after all that then put your other stuff back on your mac.

But as i said in the other thread you should upgrade your HDD to 200GB if you can, And there are loads of guides floating around the internet (Apple.com and The Forums)