Martin - from Robstown, TX
If you are talking about the cream cheese layer over the crust, that is generally spooned into the crust, then smoothed with a spatula. This is usually then topped with berries, nuts, crumbs, streusel, etc.
If you are adding a cream cheese decoration on top of these layers, an Open Star Tip (Nos. 14 – 22 or 1M) can be used to make a star or a swirl of cream cheese icing.