Go to `Applications` - `Utilities` click `Boot Camp Assistant` follow the step by step instructions 

 - Format the partitioned drive first
 - Give the partition at least 40GBs
 - Make sure you have a valid copy of windows 

If you need more help here are a couple of videos with step by step instructions:

* [How to Install windows 10](https://www.youtube.com/watch?v=ShdKIMA7gz0 )
* [Make a Bootable USB_Drive](https://www.youtube.com/watch?v=X9w3sFsiaA0)