Apple has made a very clever ploy in it's new Apple music services. Once you upgrade to the new iOS, you get an option to subscribe for Apple music services for free. But this free subscription is only for 3 months. Once you are subscribed, you are put on automatic renewal after 3 months of free subscription.
Turning off the automatic subscription
Turn off this automatic renewal feature in case you did not like the Apple music services. Or else you will be charged monthly for this service.
In iTunes store
Go to Manage subscription
And turn off automatic subscription