The reason that this method works is because it silences the thinking of the left hemisphere of your brain. The left hemisphere is associated with math, language, and organization. The right hemisphere is great at  being creative, spatial skills and intuition. The two sides have very different ways of thinking. The reason the right side of your brain does not always get a chance to prove it is artistic is because the left hemisphere is taking over the task. (Much of education develops the left side of the brain only because it deals with organization, reasoning, language, verbal skills, math and so on. You've learned to use the left side! In this case I'm telling you don't use it!) The way that the left hemisphere is silenced by this method of drawing is by making you view the picture within the confines of each square. By doing this, you can more easily see the shapes, curves and directions of the lines without naming the object in your mind. The left hemisphere is great at naming things. Naming the object however is like telling the Right hemisphere to shut up. The right side of the brain is more visual without categorizing shapes with names and perconeptions about what it should look like. When your right hemisphere is in the driver's seat, you can see things for what they really are and look like and this is how you have to see if you're going to draw what is there. First you have to see it! To really see it is a big step towards drawing it and without seeing, your drawing will be terrible. If you want to draw a foot, do not think, I am drawing a foot.. now I'm drawing the toe.. now I'm drawing the heel. This isn't good if you want your drawing to look like your reference. Think more along the lines of: "this shape is smaller than this shape, this line is very close to this line and in relation to this shape's size, this shape is larger." When you're drawing, always try to compare one shape to another in it's size and position on the page in relation to other shapes. Get to know the shape and personality of what you're drawing, knowing it's name does no good at all. It's all about your eye.	Sometimes rendering the shapes and forms of a picture can take a while. An old way of quickly getting it right is by using the grid method. You can do this with any 2 dimensional image like for example, a photograph. It's best for the image to be accurately square for the grid to work. Let's say your photograph is an enlarged 8 1/2" x 11". Using a ruler, start at the edge of one side and make a tiny mark for each inch. Do this around all sides. If one of your sides happens to  end in a half inch or anything less than an inch, then make sure it is matched on the opposite side directly across from it. For photos you can do this in pen or a very sharp pencil.     When the marks are all made all around the edges, find a ruler that is long enough to reach both sides of the picture in all directions. Use this ruler to make the lines through the picture using the marks on the edges.      When you have the reference picture all set up with the grid, then it's time to grid your destination surface. Whether you're drawing or painting it doesn't matter. The grid can be used for pictures made by both of these mediums. Make sure your grid marks on the destination surface are very light pencil. You may want to erase them from the finished drawing later. If you plan to do a painting using the grid never use pen because it will show through the paint. If you want to leave the grid behind the painting for some reason, that is fine but just know that you can't paint over it easily. It will haunt you!      Now, if you want your resulting art to be the same size as your reference photo then do the marks around the edges in the exact same measurements of 1 inch per square. If you want to enlarge the photo 200% then make a mark for every 2 inches, making each grid square 2 inches instead of 1. This can obviously be adjusted to whatever enlargement percentage you want by increasing the size of your grid squares on your destination surface.      Transfering the image in pencil; square by square. When both grids have been made, you're ready to put the 2 side by side and begin drawing by each square. Compare each line to the edge of the grid square and see how far away from the grid line it is. A great deal of the benefit I've found in the grid method is in comparing the lines of the picture to the square it's in. This allows for measuring small details well instead of approaching the picture all at once and having nothing to guide your measurements and proportionate comparisons.     When you're doing a drawing using the grid, you might be left with the unattractive grid marks on the drawing when you're done. This is why you should mark the grid lines very lightly on your paper or surface so that you can erase them from areas that you want to leave white. Pencil can be painted over. If the pencil is too dark, it may muddy your white paint just a little so be careful not to make the marks too dark. An F pencil is good for grid marks on anything being such a light pencil.
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