How can I cancel my subscription? Easy. go to ‘My Account’ page or ‘My Subscriptions’ and CANCEL SUBSCRIPTION. You can resubscribe at anytime.
That's no problem, go to your ‘MY SUBSCRIPTIONS’ and click SUSPEND. When you are ready to resume, simply reactivate your subscription on this page. You can cancel your subscription here too. You are in control.  
Can I change the products in my subscription? Easy, just add the products you want by ticking “add to existing subscription” and deleted the the product you don’t want. Manage your subscription on the MY SUBSCRIPTIONS page
Can I add products to my existing subscription? Sure, just tick "add to existing subscription"  on the product page. You can also add everything in your shopping cart to an existing subscription by selecting that option at the cart page. Manage your subscription on the MY SUBSCRIPTIONS page