Identify which information you would like to find first in the pictograph. For example, if the bar graph compares the amount of money a number of companies brought in during 2010, find the company on the left side of the bar graph that you want to learn about first.
Match the picture that lines up with that part of the graph with the key. For example, the picture for one company might be soccer balls because that's what the company manufactures. If you look in the key, you might find that a picture of a soccer ball means $10 million and a picture of a half soccer ball means $5 million.
Count the number of pictures or half pictures in the row. Use the key to determine what number this equals. For example, if there are five soccer balls and one half soccer ball, the first company would have brought in $55 million dollars during 2010. Repeat this process with each piece of information on the pictograph.