Your invoices are automatically generated and emailed to you. They are also viewable in your account when logged in.
Memberships work on academic cycles. If you are signing up for the first time you will need to choose whether to licence your school immediately or for the next academic cycle. If you opted for immediately, you will receive an invoice straight away. Upon the clearing of your payment, your account will automatically go live and run until 31st July. If you opted for the next academic cycle you have until 31st July to pay your invoice, your account will then automatically go live on 31st July and remain active for a whole year.
For renewals, all accounts renew on 31st July (regardless of when you initially signed up). You should therefore pay your invoice before this date to ensure your account remains live.