On a pocket watch, like many other clocks, the hour and minute hand are held in place by a small post in the centre of the watch face. The post is controlled by the clock mechanism and moves the hands to the correct location. Typically, the hands are held in place by very little, and it is possible for them to jar and become loose. Tightening the hour hand on a pocket watch is a straightforward repair you can do at home if you are patient and take care not to damage the watch.
Inspect your watch to determine the best way to open the face. Some pocket watches have a simple spring clasp that you press to open the face. Other watches have a dust cover protecting the clock face and hands, which you must remove before you can access the mechanisms inside the watch.
Press the button to open the watch face, or locate the groove that holds the dust cover in place. Insert the blade of the small screwdriver into this groove. Pull gently to pop the dust cover off the watch face. Set the cover aside.
Push the hour hand down firmly but gently until it pushes back into place along the watch hand post. You may have to push the hand itself, or you may be able to push the entire post gently to get the hour hand to tighten again. Take care not to push the hand extended from the post, or else you could bend it or break it off. Only apply pressure near the centre post.
Replace the dust cover or close the watch lid to finish the repair.