Motion lines are a crucial part of drawing any type of action within your comic. They vary from the simple one line to the more complex, full background motion lines. To the right is an example of the single line of motion. One could add more lines but one gets the point across just fine.
There are four ways to depict motion, the first being the line showing the path of motion as shown below. The second method is to draw multiple images of the person or thing in action in different intervals of movement along with the standard motion lines (second image below). The next image builts on the previous wherein the multiple images now are less defined and become streaks. The last method is the most widely used in manga’s: the moving background.
Then there is the other motion line that is part of the object moving as depicted to the right. The motion line should move in the direction to where it is going. The elbow, for example, if moving to the right, the motion line should also move similarly. If the elbow was moving diagonally, the streaks would follow suit. A real life example would be to swing glow sticks around where an after image trails the actual location of the light itself.