Why as no one mentioned making a nest box? It is the best way to ensure your varanid has a proper spot to lay its eggs. The easiest way to make a nest box is to buy a suitable sized rubbermaid bin, cut a hole large enough in the lid for your varanid to get into the bin. Fill the bin with with damp coco peet and play sand. 75% coco peet and 25% play sand. Put the nest box in an area where the temps will be around 85 degrees inside the nest box.

9 times out of 10 monitors will choose a nest box to lay in over other part of the cage. It will save you from digging out an entire cage of dirt and will more than likely keep your varanid from retaining its eggs.