If you signed up, you should have received an email with an active link for subscription management.
Dear Xxxxxx,
This email confirms your order of the following subscription with a free trial of 3 months. You are not charged for the free trial period, but when your 1 month subscription auto-renews on 09/30/15 you will be billed $9.99 for the period.
Name of Subscription: Individual Apple Music membership Content Provider: Apple Inc.
Date of purchase: 06/30/15
Subscription Period: 1 month
Length of Trial: 3 months
Renewal Price: $9.99
The subscription period will automatically renew unless you turn it off no later than 24 hours before the end of the current period. To cancel auto-renewal or manage your subscriptions, click below and sign in.
Manage Subscriptions
Regards,
The iTunes Store team