In this post I will show you by pictures how to install Windows 8 on Windows 7 or Windows 8 step by step.

Before install you should have the Windows 8 installer from MS, you can download by the links below:

Use the newest version: 

Windows8-ReleasePreview-32bit-English.iso (2,5Gb): http://iso.esd.microsoft.com/WRPDL/D29D6C5B1D8AF956B5DA9DF738CFD92DFD4F6C8FB/Windows8-ReleasePreview-32bit-English.iso

Sha 1 hash — 0x8BED436F0959E7120A44BF7C29FF0AA962BDEFC9

Windows8-ReleasePreview-64bit-English.iso (3,3Gb): http://iso.esd.microsoft.com/WRPDL/D29D6C5B1D8AF956B5DA9DF738CFD92DFD4F6C8FB/Windows8-ReleasePreview-64bit-English.iso

Sha 1 hash — 0xD76AD96773615E8C504F63564AF749469CFCCD57

Product Key: TK8TP-9JN6P-7X7WW-RFFTV-B7QPF

Software to check update version: Windows8-ReleasePreview-UpgradeAssista: http://view.atdmt.com/action/FY12_WinCon_Windows8Preview_DLButtonTag?href=http://go.microsoft.com/fwlink/?LinkId=242045

Software to check Sha 1 hash: http://www.mediafire.com/?csticiay58gl775

Microsoft home page: http://windows.microsoft.com/en-US/windows-8/iso

Install Windows 8 on Windows 7:

When finish download, use winzar extract ISO file to Win8 folder and store in any hard driver excluding C driver.

Restart computer then press F8 để vào Advanced Boot options the do as pictures below:

Install Windows 8 on Windows 8:

Mount ISO file to virtual driver, click to Windows 8 virtual driver then copy all file to another folder on hard driver.

Start to install:

Step 1: Click Settings/Change PC Settings (See at bottom on the right)

Step 2: Click General/ Restart now (in Advanced Startup)

Step 3: Click Troubleshoot/ Advanced options/ Command Prompt

Step 4: After restart, choice your account (enter password if any) then click Continue

Step 5: From this step you will do like install on Windows 7

The processing of install will finish after few minutes.

Goodluck to you!