To create a new procedure (later on you can switch it to a stored function), click on the Stored Procedure () icon on the Main tab of the Ribbon. Your mouse cursor will change its appearance. Click on the diagram area to create a new stored procedure. A rectangle with the name of the stored procedure will appear in the diagram:
(Optional). To switch procedure to the function double click the routine rectangle. The Stored Routine Editor will be shown. Go to the Definition tab and select Function from the Routine type drop-down list. Click OK to save your changes.
To edit parameters of the stored procedures and functions use Stored Routine Editor.