A USB stick of any size can be used because this procedure installs an "image" of the original operating system onto the stick. Both the installation software and the "image" file must be downloaded before installation.
First download the "image" file G498.zip. This zip file contains a disk image of a drive that’s formatted with the new operating system. After downloading it, right-click it and select "Extract All" from the menu that pops up. It will create folder called g498 in the same folder that contains g498.zip. In the new folder will be a file called g498.img. Be sure to note where your browser downloaded the file because you will need to navigate there from the installation software.
Next, download the imaging software. Double-click it and follow the instructions that come up to install the Win32 Disk Imager program.
Check the box that prompts to create a desktop shortcut.
Once the disk imaging program is installed, put a USB stick (at least 2GB: no matter how big it is it will look like a 2GB stick once the image is installed) in your computer. Double-click the Win32 Disk Imager icon. It will open with an empty dialog near the top of its window, labeled “Image File”, with a small folder icon next to it. Click on the folder icon to bring up a File Explorer window. Navigate to the g498.img file and click it, then click Open. Click the Write button and the image will be written to the USB stick. This takes quite a while. Once it’s completed, close the imaging program. If you intend to use this USB stick to reformat harddrive, click here for next step in that procedure.
Step by step instructions to write "image" to drive, with screen shots: