1. Boot your computer from Windows Vista DVD or CD.
2. On the Install Windows page, click Install now.
3. On the Get important updates for installation page, we recommend getting the latest updates to help ensure a successful installation and to help protect your computer against security threats. You will need an Internet connection to get installation updates.
4. On the Type your product key for activation page, we strongly recommend that you type your 25-character product key to help avoid problems during activation.
5. On the Please read the license terms page, if you accept the license terms, click I accept the license terms.
6. Follow the instructions on each page. On the Which type of installation do you want? page, click Custom.
7. On the Where do you want to install Windows? page, select the partition where you want to install Windows.
8. Click Next to begin the installation. Then follow the instructions.