But I doubt that an operating system could fit into a flash drive.
Maybe if you used an external hard drive.

nice…….
1. Your Laptop MUST have a BIOS that supports BOOTing off a USB port !
2. You need a big USB storage device DVDs = 4.7GB so try a 8GB USB device.
2a. Note, some DVDs are 7.96GB
3. Copy your OS install DVD to your USB device
4. Copy your Laptop drivers to your USB device
5. Copy your OS personal setting to your USB device
6. Copy your Apps DATA (DOC, Photos, URLs, XML’,…….) to your USB device.
7. Back-up your system’s HDD to disk or the Web !

Up-Date your BIOS boot order to BOOT from your USB port, power down, power up

I hope this could help you
Regards

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make ur usb bootable and put the format files in it and do what u want