Coax the muscles, do not force them.
If undue force be used in an effort to secure quick results, the muscles will toughen, and your object will be defeated.
Just pull or press, as the case may be, following the directions as closely as possible, looking all the time for the particular muscle to appear. As soon as something like the pose has been secured, try to fix your mind upon the exact manner in which you got the result, and relax the muscles, and try to get the pose again in the same way.
Only use a mirror to discover if you have secured the desired control, and not for getting it. Those students who always exercise before a mirror are never confident of getting an exact pose without its aid.
The mirror should be there, placed in such a position that a turn of the head or eyes will show whether the pose has been correctly secured.
If the pose is unsatisfactory, turn the eyes or head away and try again, until you get the muscle or muscles controlled through the feeling, and not the vision.
Before going on to the actual exercises of control, my final advice to the student is:
STUDY ONE EXERCISE AT A TIME AND PRACTICE PATIENCE
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