Just login to your brushette.com and under your account you'll see the option.
You don't need to contact the support service or to wait 48h the time your email is taken into account, hit cancel and you won't be receiving anything from us anymore.
You can cancel at anytime all subscriptions, except the ones you pre-paid for. Indeed if you pre-paid for a quarterly or yearly plan chances are high that you got a discounted rate from the month-to-month plan.