Approval cycles are saved behind users on the page "Users" or behind cost centers on the page "Cost Centers". If a saved expense has a cost center that has an approval cycle behind it, the expense will follow this cost center's cycle instead of the cycle saved behind the user.
The approval cycle may contain as many people as needed. You can add more approvers by pressing the button "+add approver".
You can also choose in which order people appear in the approval cycle. If you choose the "Then" rule, person A has to approve the expense before it goes to B's approval. With rule "Or", only A or B has to approve the expense.