Everything must be harmonious, and a spotty appearance is to be avoided.
For instance, a very light effect of hair and face with a moderately dark dress and a jetty-black background is very bad. Also, a head with black hair, white dress and very light background. All violent contrasts should be avoided.
Put the background in at first with charcoal only, using parallel lines in one direction, then crossing them diagonally. After this take the large stump and rub these lines into one tone, yet leaving a slight suggestion of the lines to show through.
Put in this tone only around the shoulders and lower part of the head, leaving the upper part of the paper bare, or nearly so.
In this way try the effect, working slowly and adding more charcoal as the tone needs to be darker.
When you have decided that the background has the right effect in relation to the head, use the crayon point in the same way as the charcoal, putting in crossed lines and rubbing them together again with the stump until a transparent effect is achieved, which will give atmosphere and relieve the head.
If you get on too much crayon rub it all over with a soft rag. This is an excellent thing to do occasionally, as it softens and unites the whole while making the tone lighter.
Sometimes in finishing, a few touches of the rubber point may be used at the edges of the background and where it softens off at the top. Use the rubber in the same manner as the crayon point, making light lines crossing obliquely.
Remember that hardly any appearance of lines must be seen. When all is done they must be so softened with stump and rag as to present almost the appearance, at a little distance, of an even tone.
In some cases the background may be carried up higher than the middle of the head, but it is very rarely necessary to surround the whole head with it.