Is this your board? http://www.asus.com/us/Motherboards/Z87MPLUS/
If so, that board has software available for updating the BIOS. You can find it for download here: http://www.asus.com/us/Motherboards/Z87MPLUS/HelpDesk_Download/
But it is probably already on the disk that came with your motherboard. And the instructions are found in your motherboard manual around page 2-13. "BIOS Update Utility"