You will need:
Horizon
A map
Common sense
A flash drive (setup on xbox)
An xbox
Minecraft xbox 360 edition
How to do it:
1. On your xbox, copy the profile you will use onto your flash drive.
2. On your computer, open Horizon.
3. In Horizon, open the device explorer, open Games and apps, then click on Inject new file.
4. Now navigate to the place you downloaded your map.
5. Select your map and press ok.
6. Wait.
7. Now choose the profile you copied on earlier.
8. Click on use this profile.
9. Wait.
10. Click OK.
11. Your map should be on your hard drive now.
12. On your xbox, play it.