Boot From External USB Drive or USB Stick

Hi friends,

I have the Inspiron 15 3000 Series (Intel) - 3567 laptop.

I want to boot from a USB (Linux distro) either a stick or a hard drive connected by cable. 

I could use help configuring the BIOS because this has been difficult to sort out.

Any help files or assist you can provide will be greatly appreciated.

Thanks,

BORNTODEAL