You can either create a new supplier in Xero, or use Opsyte.

Creating a new supplier in Xero: If you chose to add a new supplier in Xero, please make sure you click the button below to re-sync the suppliers in Opsyte, so we always have the most up to date data.

Creating a new supplier in Opsyte: You can add a supplier by using Opsyte in two ways. The first is by clicking on the 'Create New Supplier' button on the invoice page and filling in the form. This adds a new supplier into Xero and Opsyte.

An easier way is to find a supplier that hasn't been added to either Xero or Opsyte, and clicking on the green '+' beside the supplier's name and clicking on 'Create'.