How to set BIOS password on Windows 8.1/8 to ensure security

We all know that when we upgrade our Windows system to Windows 8.1/8, it demand a higher security level. So I want to know how to set a bios password on Windows 8.1/8 to ensure security. I have heard a tool for Windows password reset can do it, it named Windows Password Key. But I don't know whether it works for me. Can you give me some advices.