A gateway can be added using existing activities/ process links or events. OR it can be created with new activities as explained below.
Quick Steps to Create a Gateway with New Activities
Select one of the following methods to open the Gateway Popup:
Keyboard shortcut: ALT+G
Plus icon on the map: Hover over the connector where you want to add the gateway and select the green plus icon:
Green action button: Click the add gateway action button found left of the map

From the right-hand side diagram content menu: a plus sign appears between activities. Select the one where you want to add the gateway

A gateway will appear consisting of two rows that each contain one default activity. These activities can be edited to add a title and details. See video:
Note
Gateways cannot contain decisions.
