Draw thick solid contour index lines on your map. These lines are spaced according to a set amount of elevation change. For example, if you are mapping a mostly flat terrain, the distance between contour lines may only amount to 5 or 10 feet, but if you are mapping a mountainous area the difference between lines may equal 100 feet or more. Make small breaks in the index contour lines and write in the exact elevation of that line. The line should always stay at that exact same elevation as it winds around the map. When lines are closer together, it indicates rapid elevation change and when they are far apart they show that the elevation change is gradual.
Make intermediate contour lines between far-apart index contour lines to show elevation changes that are gradual and happen between the index lines. Intermediate contour lines are drawn in lighter and thinner than index lines and do not list the actual elevation. You can draw as many intermediate contour lines as you want between index lines to show gradual slopes, but be sure that, like the index lines, the intermediate lines always stay on the exact same line of elevation as they wind around the map.
Draw lines with inward-facing dashes to represent depressions, craters, holes or other loss of elevation features on your map. These dashed lines, called hachures, indicate that each line is actually going down in elevation instead of up. Use as many of these hachures as you want to symbolize a loss of elevation but when they cross a marked elevation threshold, as denoted by the contour index lines, write in the value along the hachure line.
Draw a dotted line to indicate very small elevation changes in a relatively flat surface like a field or plain. Dotted lines are used to show subtle contour features on topographical maps and can help people identify the highest point or a natural dip in an otherwise relatively flat area of the map. As with all the other contour lines, make sure the line itself follows the exact elevation value the whole time.
