Decide how large you would like your grid to be. It should consist of perfect squares of equal size. Use smaller grid lines (such as a half-inch squares) for more intricate work that requires excessive detail. However, if you are drawing a landscape and only need to use the grid as a general guideline, keep the grid squares larger.
Measure both your photograph (or other picture you want to copy) and your grid paper. You need the same number of squares on the paper as on the photograph. If your drawing paper is 18 inches by 21 inches and your photograph is 5 inches by 7 inches, draw the grid over 15 by 21 inches of the drawing sheet to have a proportional area three times the size of the photograph. Or cut the extra 3 inches off the drawing sheet.
Mark the edges of the drawing paper with your ruler and pencil. If you decided to make inch-size grids, mark your paper off every inch on all sides. Use a light-lead pencil, such as a 4H pencil. This will allow you to erase it more easily.
Connect the markings on each side of the paper (connecting the first marking on the left side and the first marking on the right side, and so on) with the ruler. Draw a light line from one to another.
Perform this connection with every set of line markers, both left to right and top to bottom. You will be left with a grid made up of inch-size squares.
If your drawing paper is three times the size of the photograph and you want to use 1-inch squares for your drawing sheet, the squares on the photograph should be 1/3 of an inch. Mark these off on the photograph just as you did on the paper. You can use transparency paper to draw the grid over the photograph or make a copy to draw the grid on.