How to Enter BIOS menu on a most Sony Vaio E series laptop so that I can boot from USB?

1. **Shutdown Your Computer**: Ensure that your laptop is completely turned off.
2. **Press "ASSIST" Button**: Instead of the power button, press the "ASSIST" button on your Sony Vaio E series laptop.
3. **Access the Assist Menu**: This should bring up the Assist menu, which provides options for various system utilities and settings, including BIOS access.
4. **Enter BIOS**: From the Assist menu, select the option to enter the BIOS. The specific key or option to access the BIOS may vary, but commonly it appears as an option in the Assist menu.
5. **Navigate to Boot Options**: Once you're in the BIOS menu, navigate to the "Boot" or "Boot Options" section.
6. **Set USB as First Boot Device**: In the boot options menu, locate the option to change the boot order and prioritize the USB drive as the first boot device. This ensures that your laptop boots from the USB drive when it starts up.
7. **Save and Exit**: After selecting the USB drive as the primary boot device, save your changes and exit the BIOS menu. Ensure to follow the prompts to save changes.
8. **Restart Your Laptop**: Once you've saved the changes and exited the BIOS menu, restart your laptop.
9. **Boot from USB**: Upon restart, your laptop should boot from the USB drive automatically if it's properly configured in the BIOS. Follow the on-screen instructions to proceed with booting from the USB drive.
By following these steps, you should be able to access the BIOS menu on your Sony Vaio E series laptop and boot from a USB drive. If the "ASSIST" button doesn't work, you can also try using the "F1" or "F3" key as alternatives, as you suggested.