Q: how to update boot camp

I picked up my new macbook pro this morning (12 inch 750GB Mid 2012 OSX Yosemite 10.10.5), and I’ve been trying to dual boot it with Windows 10. I’ve downloaded the ISO from Microsoft and formatted my USB stick to FAT. However, I keep getting errors in the bootcamp assistant. It either gets stuck while downloading the Windows Support files or says the Windows Support files could not be saved to the selected drive. after i check version of my boot camp assistant it version  5.1.4 (500).

Any help?

thanks,