How do I cancel my subscription?

Go to Account → Subscription and click Cancel subscription (top right), then confirm. Renewals stop straight away and you won't be charged again; your plan and store stay active until the end of the current paid period (the date is shown in the banner). To keep the store live after that, pick a plan on the same page. Only users with billing access see this page, and the button isn't shown on a trial, free period or free plan.