This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
366. Simplicity is the keynote of successful figure posing. The more simple the pose the more natural and pleasing are the final results. The one aim is to reproduce the subject in the most characteristic manner possible. The value of any style of portraiture is determined, to a great extent, by simplicity and correct drawing.
367. Special attention must be given to the manner in which the various lines are formed, so that all lines are broken, and no marked parallel lines exist. As an example, the arm should not hang perfectly straight, but should be bent slightly at the elbow. If the arm rests on a chair, or other accessory, care must be exercised to avoid right angle, or L-shaped, lines being formed. Do not permit both arms to extend in the same direction, or to occupy exactly the same position. Curves and lines may often be broken by the addition of drapery, or some accessory, sufficient to avoid the monotony.
368. As the face is the most important feature of a portrait, it should receive the greatest degree of attention. Place it in the strongest light, with all other portions of the figure sufficiently subdued to hold them in subjection to the face. If the hands are too much in evidence and any difficulty is experienced in overcoming this prominence, arrange the arms so that the lines formed will not detract from the face.
Posing The Hands. Always give attention to the position of the hands, as they are most important, and if improperly placed are quite sure to ruin the resulting picture. Arrange them so when photographed they will appear as small as possible. Never turn the back or broad side of the hand to the camera. On the contrary, allow only the smallest and most narrow side to face the instrument. Turn them in a way to show the edge and not the broad side. Do not allow the hands to hang at right angles to the wrists; they should curve gradually and gracefully. Never allow them to be tightly closed; rather open the fingers, yet always have them slightly bent. Only the index finger may be quite straight. Observe the characteristic position in which people hold their hands when walking, and you will see that they are not doubled up tightly, nor are the fingers extended absolutely straight.
370. In standing figures, where the hands are placed back of the subject, do not have them clasped together at the back so they cover the waist line. Arrange them so that the elbows will be bent. However, never have both elbows bent at the same angle. It is better that one arm be more straight, or rest on some support. This will break the curve and give better lines. An easy and natural position for a lady is to gather the skirts in one hand just enough to give it the appearance of doing something. With the one hand so occupied, the other may hang perfectly straight and give good lines. The straight arm should always be turned into the shadow, as it is then less conspicuous. Whenever possible, give the hands something to do; otherwise they are liable to attract undue attention.