You might of noticed the "Order" when creating an advertisement.
The order dictates in which order the advertisements will appear.
They will displayed in between regular posts respecting the order.
To change the order:
You can write directly in the Order column and click Save.
Or select one and Pencil to edit.
Grouping publicities in the same advertising post:
If some publicities have the same order, they are grouped together.
An advertising post can contain up to 4 publicities. If there’s more than that, 4 of them will be randomly selected.
To group them together, give them all the same number. For ex: 2,2,2