YOU WILL NEED THE FOLLOWING :-
-A USB Flash drive of just about any GB (preferably 8)
-A PC
-A Modding Program Called Horizon

1)Move Your profile to your USB.
-Dashboard>Settings>System>Storage>Hard Drive>Profiles>Click on Your Profile>Move>Flash Drive-

2)Download horizon on your PC!
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3)Plug Your USB Flash Drive into your PC and exit out all the things that pop up (sometimes nothing pops up)

4)Download A Map From The Internet(Preferably YouTube)
BUT MAKE SURE ITS FOR XBOX AS PC MAPS WONT WORK!
5)Drag the map to your desktop.

6)Open Horizon and open the device explorer.

7)click ''Inject New File''

8)A little tab should come up and on the left hand side click ''Desktop''

9)Select the map you downloaded!

10)Your profile will come up and click ''Use This Profile''

11)Wait for it to be injected (it will usually take 10 seconds max)

12)Once it says your map has been transferred take out your USB and plug it into your xbox 360.

13) go to storage and click on Flash Drive and go to profiles and select your profile and click move then hard drive.

14)then go to Games and Apps and go to Minecraft and select the map you downloaded and click move and move it back to your hard drive!

You can now launch minecraft and hit ''Play Game'' then hard drive and the map will be there!