a system for sketching , illustrating , drawing or painting likeness compositions such as canvas oil paintings from source images includes a set of increasing size reusable overlayable source image grids with image composition frames used with corresponding destination canvas grid patterns , allowing a consistent grid pattern for all canvas sizes by using predetermined grid dimensions for each canvas size . the image grid patterns may be affixed to clear plastic sheets or may be software - generated patterns . this combination greatly simplifies the use of grids in artwork and provides low - cost timesaving methods to draw accurate perspective . the system includes a unique canvas grid ruler for simplifying generation of canvas grid lines and in some embodiments canvases are pre - printed or backside - shadowed with appropriate canvas grid patterns and labels .