First you will have to go to BIOS, power on your laptop and press multiple times the F2 Key.
Second under Boot tab disable Secure Boot, then if Operating System you want to install is Windows 8 choose UEFI, if it’s an older Operating System choose CSM. Exit Saving Changes.
And thirds, to boot your USB Device, go to tab Advanced and disable: Fast BIOS Mode, this option Enabled will skip searching of any bootable media and drives. Exit Saving Changes.
To Restore all settings, go to tab Exit, and press Load Setup Defaults. Exit Saving Changes.