On the screen below you will see the Debtors menu tree. The Debtors menu tree will give you an ability to prepare an invoice, credit note, process receipts, do a journal adjustment and to view the ledger which is in fact the enquiry screen. The setup is where you would need to set up various aspects for billing.
For example the billing entity, SKY software works on the basis that you can have multiple billing entries against each record. There is also a place where you can set up your fee paragraphs. This is automatic narration that you can use for your invoice.