In the Gossh Options » Footer Settings » Footer Layout field you can select the layout for the widget area. You can either select the number of columns that this area will contain or you can disable the widget area by selecting the “No widget footer” option.
If you select to display a widget area, you can then go to “Appearance” -> “Widgets” to add widgets to the footer. If, for example you have selected a “Three columns” layout, in the Widgets section you will see three widget areas called “Footer Column One”, “Footer Column Two” and “Footer Column Three”. After this you can drag and drop widgets from the left to any of these three boxes.