You use a viewfinder to find and isolate a scene so that you can draw it. It helps you focus on the scene by blocking out the visual clutter in the area around the section you want to draw. If you mark the inside edges of the viewfinder into sections, it's easier to transfer exactly what you see. An index card with a 11 ⁄2-x-2-inch window cut out works very well for an 18-x-24 or 9-x-12-inch sheet of paper. If you want more flexibility, you can configure two L shapes cut from cardstock or mat board for any rectangular format.
If you're using a viewfinder made from an index card, you can divide the window into quarters by taping a horizontal thread and a vertical thread across the center sections of the window. Then lightly draw a horizontal line and a vertical line from the center edges of the paper. Transfer what you see in each quarter to the paper, paying close attention to where the lines of the initial drawing are positioned along the edges.
To use your viewfinder, follow these steps:
1. Hold the viewfinder so that any ruler marks you made face you and look through the window viewing area at your subject.
2. Move the viewfinder around the arrangement trying different views until you find the scene you want to draw. Treat the viewfinder like you do the viewfinder in your camera when you're finding the right shot to take, turning and moving it different directions to fit in the pieces of your arrangement you want in your scene.
3. Compare the markings on your viewfinder with the objects in your scene and find two points that you can keep lined up as you work. For example, the top of a bottle may line up with the halfway point on the edge of the viewfinder, and maybe the handle of a spoon is positioned at one corner. This tactic helps you maintain the same view or return to it if you move your arm or leave the drawing before you have finished blocking it in. While you're at it, mark an X on the floor where you stand or sit with easy release masking tape so you can always set up in the same place. You can't get an accurate lineup of your key points if you start from a different position during every session.
4. Lightly mark these key viewfinder points on the edges of your rough sketch and your drawing. These marks can help you transfer and maintain the general positions and proportions of your objects as you see them in the viewfinder.