Once cut you will want to tape down the poster board to a drawing board. I recommend a drawing board because you are able to rotate it, and angle the board while drawing which makes it more comfortable, especially if you are working on a large surface. After securing the poster board to the drawing board you will want to lay out a light grid on your poster board. I stress "light grid" here because you will need to be able to erase the grid as you progress so that it doesn't show up in your final project. Mechanical pencils are great for this type of layout as their lines are fine and easier to erase. Use your T-square to make sure that your grid is plumb and square.

To determine how big your grid squares should be you will need to take the enlargement factor, 3 in our example, and multiply it by the size of the squares used on the original print grid, 1" in our example. So the grid for the example enlargement would be 1" multiplied by 3, or 3" squares. After laying out your grid on your poster board you will need to number and/or letter your rows and columns to match those on your original print grid.

Once your drawing area has been prepared, you get to start drawing. The matrixing process is simple. Just recreate what is in each square of the original print inside the corresponding grid square on your poster board. You may be thinking why is this easier then trying to draw the whole image without a grid? The answer is that by reducing the viewable areas in a grid your mind is only seeing shapes and not figures. It is easier to draw and reproduce shapes than it is images. Also by having the grid you know where lines should meet, where shading should go, and where lines and curves should be placed within a smaller space. This will help you to recreate what is in your original print perfectly, or at least close to perfect.