Easily enter BIOS settings using a hotkey: Access BIOS to adjust system setup so you can do things like setup USB Boot. Computer suppliers and motherboard manufacturers may use varying keyboard hotkeys or key combinations that can be pressed during system post to open BIOS.
USB Boot Manager; How to Access the Boot Menu on a Phoenix Award BIOS to select a USB flash drive as the first boot device. The following covers how to boot with USB.
The following list of USB BIOS Boot Setting and Options have been thoroughly tested with various Linux USB installs. There may be others but this is meant to be a simple checklist to familiarize you with the boot options and which ones to use.