Steps
Go to Spend → Bills and click Create Bills → Create manually.
Under Document details, fill in:
Title: what the bill is for, e.g. Office rent - October.
Document number: the vendor's invoice number, or leave it blank to auto-number.
Currency, Date and Due date.
Vendor: choose from your contacts.
Under Line items, add each cost: item, quantity, amount and the expense account it belongs to (e.g. Rent expense, Software and subscriptions). Add tax or a discount if needed.
Optional sections:
Record this as a prepayment: for costs you pay upfront that cover several months, such as annual insurance.
Add shipping information.
Add payment information: if you've already paid part or all of it.
Split account: share the cost across two accounts.
Classification: Branch, Employee, Department and Project.
Memo: an internal memo and a Note on document.
Attachments: attach the vendor's invoice. Recommended, for your audit trail.
Click Save as and choose Create, or Save as Draft to finish later.
What happens in your books
The cost goes to the expense account on each line, and the amount you owe goes to Account payable. When you pay, the balance moves from payables to your bank or cash account.