You are normally given this tool when you purchase from the online Microsoft Store. The easiest way to turn a USB flash drive into a bootable Windows 7 installer is by using the tool Microsoft offers, cunningly named the Windows 7 USB/DVD Download Tool. To get started, download the installer [exe] from Microsoft.com and follow the basic steps to put it onto your computer; you can put it on the computer you plan to install Windows 7 on or another one, it doesn't matter. Step two is straightforward: simply choose USB device. In step three, all you have to do is make sure that you are choosing the correct USB device. If you have other data on the device, move it to your hard drive, another USB device, or somewhere else before proceeding. The tool will prompt you if it detects data on the device. Once your data is backed up elsewhere, click Erase USB Device. You will get another prompt warning you that all the data will be wiped. Click Yes to continue.