Here are some images that offer some insight into what a scan looks like once it is marked out.
Cardboard can be utilized over areas that are difficult to mark out. In the above picture the red marking indicates a powered conduit.
The orange circle in the above photo indicates the intended cutting area. The scan shows how close items within the concrete are to the cutting area.
In the above photograph the depths of items are marked out. Scanning gives information on how deep items are within the concrete.