Free Printable Protractor | Measuring Angles Worksheets | PDF A protractor has two scales, one for degrees and one for millimeters. You should align the 90-degree scale on one side of the protractor with the 0 degree line on a map, which is located on the right side. Then, line up the other side of the angle with the 90-degree scale on the inner side of the protractor. You will be able to find the angle ...