According to [[wp>Andrew Loomis]], in any succesful drawing, attention must be given to five P's and five C's((Successful Drawing, ISBN13: 9780857687616, pages 18 and 19)) as he calls them. 

====== Five P's ======
  * Proportion, the three dimensions
  * Placement, a position in space
  * Perspective, relationship of viewpoint to subject
  * Planes, surface appearance as defined by light and shadow
  * Pattern, the deliberate arrangement of the tones on the subject

====== Five C's ======
  * Conception, a rough indication of an idea
  * Construction, an attempt to establish the forms from life or from basic knowledge
  * Contour, the limits of forms in space, according to viewpoint
  * Character, the specific qualities of individual units of your subject in light
  * Consistency, all the essentials of construction, lighting, and pattern, organized as a unit