Some painters find squaring up their final drawings or cartoons irksome and feel that they would like to go straight on to painting up their final design. I hold no firm ideas about this. If you are confident and have the skill, you might manage to do this without any muddle. But for those who prefer to tread more cautiously, squaring up is the next step.
Squaring up a cartoon is merely a convenient way of enlarging your composition on to a canvas. Provided the proportion of your cartoon is the same as that of your canvas, by covering both with the same number of squares you will be able to transfer the cartoon on to the larger scale on your canvas. To square up simply and quickly it is advisable to have your cartoon measured off in inches, so that if it is say 15 in. x 12 in., it will enlarge up to a canvas size of 30 in. x 24 in. and you will only have to measure off 1 in. or 2 in. squares on the cartoon to be in proportion to 2 in. or 4 in. squares on the canvas.
Another method is to divide your cartoon and canvas into halves, quarters and eighths (Fig. 40). This method, however, does not give you squares to guide you but rectangles and rectangles are not so accurate when it comes to helping you to judge the drawing you are putting on to the canvas. This last method is better if you have an odd shaped composition or canvas. You can't do your cartoons accurately in inches every time.
When you have squared up both your cartoon and canvas, carefully copy what is in the squares of your cartoon on to the equivalent squares on your canvas. Numbering the squares by the edges will eliminate error (Fig. 41).
You can draw up your canvas in charcoal, making sure you blow off any excess dust or it will get into your first coats of paint and mess them up. Or you can use lead pencil, or thinned out umber oil paint and paint in your drawing with a brush. It isn't necessary to do any more than outline your composition. Any detail will only get lost with the first few coats of paint. Neither is it essential to use tone to state the masses and light and dark. But this last rule is flexible and need not be adhered to if the situation does not warrant it.