Tiles (loose layed , no glue no grout - makes it dead easy to remove soiled tiles for cleaning), and some scot-towel (paper towel) under food dish and in places the beardie likes to use as it's latrine or to nap.
In full size beardie enclosures for adults - as above.
In rearing tubs , I cover about 1/2 the the "floor" with paper towelling (2 or 3 layers).