welcome to angelthesis ... ... an ever growing fansite on the manga art style. Here, you will find clear and easy to follow drawing tutorials along with a reference library to help you with difficult poses, expressions, costumes, and more.
To draw manga, it isn't enough to simply know how to draw outlines. You also need to understand how light and shadows work to give your drawings texture and a 3D shape.
Shadows are actually fairly simple to understand. Light travels in a straight line from its source in all directions. Opaque objects will block incomming light rays, so regions immediately behind them will be darker. The darkness of the shadows depend on how much light is blocked (eg. round objects have gradient shadows because they block light little by little).
After you finish your outline, decide where your light source is. All shadows (on the objects or the ground) need to be consistently on the opposite side of this source. To estimate the length, size, and direction of the ground shadow, draw two straight lines from the light source to both sides of the object. Anything in between these lines will be shadow.
The amount of shadows on the object itself depends on the width and intensity of the light beam. Shadows will be smaller in the presence of a lot of light, and bigger when there isn't much around.
There are many ways to shade. You can smudge your pencil lines to make a gradient or crosshatch. The edges of your shadows can be distinct or blurry. Which way should you shade? It really depends on what your mood is. Each technique creates a specific feel to your drawing, but you'll understand this as you draw more.
Lastly, regions of an object that light shines upon will be much lighter. Just as shadows can give texture or a certain surface property to your drawing, so can lighting. For instance, you can tell whether a surface is smooth or not by the different regions that are illuminated. The perfect way to understand this concept is through observation and practice.
