- Obtain a ISO or DMG of Leopard (I've heard "Mac OS X 10.5 Leopard [ToH]-RC2 SSE3/SSE2 Intel Only" works great and is available on something called "bittorrent"
- Burn the downloaded DMG file to a DVD (ofcourse)
- Configure your EEE pc to boot from USB by pressing F2 at boot and configuring the BIOS
- Connect your external CD/DVD drive to the EEE pc and power on.
- From the boot screen the EEE press F8 for more options.
- From the boot prompt type "-v -x" without the quotes and press enter
- Wait 15-20 minutes for the graphical installer to start
This part is stolen word for word from Adam at Lifehacker:
Some information was taken from Dan at uneasysilence.com
Format the install drive: I know that you’re raring to install now that you’re finally here, but there’s one thing we need to do first: Format our hard drive so that it’s prepared to receive the Leopard installation. So go to Utilities in the menu bar and select Disk Utility (if you don’t have a working mouse yet, you can still access the menu bar from the keyboard). Once Disk Utility fires up, it’s time to format the drive. Here’s how:
Select your hard drive in the left sidebar.
Click on the tab labeled Partition.
Select a 1 partition Volume Scheme, name the volume Leopard, and choose Mac OS Extended (Journaled) as the format.
Last, click the Options button and choose Master Boot Record as the partition scheme.
Now that your drive is ready, so are you.
Install Leopard: This really is the easiest part—just follow the on-screen instructions and choose your newly created Leopard partition as the install destination. Then, before you make that final click on the Install button, click Customize and de-select Additional Fonts, Language Translations, and X11. These components were removed so we could fit everything on the patched DVD, so we won’t be installing them now.
That should be it, please keep in mind that all things do not work, if you really want OSX on your EEE you should some research before committing to it.