The first order of business when doing shoulder exercises is regaining full motion.   Once a full pain free motion of the shoulder is obtained, the strength of the shoulder returns routinely with or without strengthening exercises though exercises would speed up the process.  The following exercises require no special equipment, just a door and a wall.

The first exercises are designed to force the arm to go straight toward the ceiling and a door is the handiest equipment around.  To protect the hinges grab the door close to the hinges.  If short the person may need a step stool.  Do not use a chair.  Start as the picture shows with your knees straight and slowly bend the knees thus stretching the shoulder.  All these exercises are shown using the left arm, but they are equally valid if the right shoulder is involved.  If small children are around, take steps to keep the door from being pulled closed smashing your fingers.

The next exercises require only a wall.  With your back flat against the wall try with your arms at 90 degrees as seen in the pictures to first bring both arms to the wall first above and the below.  You may need help of another for this.

A third set of exercises is crossing the arm first in front of your chest and using your other arm as leverage to push it farther, trying with your left hand to reach as far over the top of your right shoulder as possible.  As stated before, this is equally valid if the opposite shoulder is involved, just reversed.  Then you bring the arm behind your head as seen in the picture.

Reaching behind your body is as hard or harder than reaching the top shelf when a shoulder is stiff and painful and the 3 pictures show the maneuvers necessary to regain this motion, which is called internal rotation.

First bring the involved extremity as far behind your back and close to the body.  You then place the uninvolved hand between the other hand and your body as shown.

You then push the hand away from your body as far as possible and keeping it away from the body help it up as high on the back as possible.

All these should be repeated frequently through the day.  This is made easier since minimal equipment is required.