Yes, Big Look is a monthly subscription with no minimum term or contract, therefore, you can cancel at any time.
If you cancel your subscription, access to Big Look courses will be revoked when the next renewal or billing date occurs in Stripe and no payment is made. For example, if you end the subscription on Sept 1 and the next billing date is Sept 30, you will have access for 30 days and then lose access on Sept 30.
You can cancel your subscription by navigating to 'My Account' and then choosing 'Billing'. form here, you will have the option to remove your credit card, thereby cancelling your subscription. If you are within your 7 day free trial period, you will not be charged for your use of Big Look.