how to install VirtualBox on Mac OS X Lion


0. disable Time Machine (this is important. Or the image file, which is larger than 10 GB in general, would be backed up wasting another 10 GB whenever any tiny modification occur to the image file.).

1. download VirtualBox and install.
I chose 1 GB ram, 10 GB disk. --> After MSOffice and Hangul editor installed, only 4 GB is remained. (Full installation of MS SQL 2008 standard r2 requires 5.6 GB for example. Only for document tasks, 10 GB is ok. If some serious task such as SQL is required maybe 30 or 40 GB would be proper.)
It is said that these can be expanded later. --> This does not work for me. I don't know why.

2. install Windows XP with Service Pack 2
Partition with NTFS.
Keyboard type 3 to enable shift-space key for hangul/english switching.

3. install vaccine program such as naver vaccine and install naver cleaner to control unintentional installing bad programs
Sometimes it is difficult to download with Internet Explorer 7 or earlier.
So Internet Explorer 8 is to be installed before.

4. install Service Pack 3 before windows update (this is important since the the update is not working before the Service Pack 3 is installed)

5. windows update
Upgrade the internet explorer to 8 and '도구' > windows update.
Or '시작' > '모든 프로그램' > windows update

6. install VirtualBox Guest Addition to enable shared folders and etc.
In the virtual machine menu bar, click "Devices" > "Install Guest Addition"

7. add a shared folder.
Select a shared folder (ex. ~/Downloads/) from the icon on the right bottom side of the virtual machine window pane.
Check read-only, auto mount, permanent options.
Reboot the windows xp. Then the shared folder appears in the explorer.

8. install basic sw such as MS Office and Hangul.
You can use 'choose virtual cd/dvd disk file ...' menu in the right bottom of the virtual machine window pane and .cdr files.
When installing MS Office, include the 'tools' element and later add mathematic equation editor to power point.
'도구' > '사용자 지정' > '명령' > '삽입' > '수식 편집기' > and drag the equation editor icon to the menu bar.
(It is said that you can insert the equation editor by '삽입' > '개체' > 'Microsoft Equation 3.0' to a slide.
But I think the above icon-dragging-to-menu-bar is more convenient for the later uses.)

9. start Time Machine's backup to backup the first completed image file of VirtualBox

10. add the folder ~/VirtualBox VMs/ to the excluded folders list in the Time Machine option

11. enable Time Machine.

Done.

ps.
12. install VirtualBox Extension Pack (for USB 2.0 support)