Unroll the map on a flat table or work table. Make sure the map is in good condition and not damaged.
Use the compass to line up the map with magnetic north. At the lower left corner of the map will be a short pair of lines that adjoin at the bottom. One line will be labeled true north and the other will say magnetic north (sometimes abbreviated MN). This symbol is called magnetic declination. Place the compass on top of the map near the two lines and rotate the map until the magnetic line corresponds with the north-south axis of the compass.
Search the map for bodies of water. Make sure the map uses the blue color to symbolize an area of water.
Read the proper name of the body of water to see how the geographical feature is classified. If the body of water is labeled as a lake, it is still necessary to complete the rest of the steps to see if the water area is a true lake and also to learn what man-made structures might be associated with the lake.
Find the outlet for the lake. That is the point where water flows out of the lake to places of lower elevation. The outlet will be located at one end of the lake and the surrounding land area will be at a lower elevation as you follow the outlet away from the lake. Contour lines along the shore can help locate the outlet if it is not obvious. It the lake is man-made, there may be a dam symbol at the lower end of the lake.
Follow the lake outlet to see where it leads. This will tell you if the water area is part of a chain of lakes or if there are more dams downstream. Being able to decipher downstream from upstream is an important map-reading skill.
Learn how to find glaciers, snowfields, submerged marshes and intermittent ponds on a topo map. Each one of these natural features might be confused with a lake.
