Eyeglasses typically use a series of screws to secure the lenses, the nose-pads and the legs in place. If these screws were to loosen, your vision could easily get distorted or, worse your lenses may end up damaged or lost. Tightening your the screws on your glasses requires only a few tools and can be done in just a few minutes.
Anchor the glasses on the straight edge of a table or of a hard surface. Anchoring your glasses involves placing one of the two outside corners -- the curves between the lenses and the legs -- on an edge. Doing so will help you avoid stabbing yourself, will keep the glasses from moving while you tighten the screws and will aid your dexterity.
Tighten the screws securing the lenses in place. Do not attempt to overtighten the screws or you could end up damaging the frame and the screws. Replace the screws altogether if their thread has worn or they might be unable to hold the lenses in place.
Attempt to tighten the leg screws. If the legs are not wobbly or the leg screws are secure, avoid overtightening them to avoid damage to the frame or the screws.
Tighten the screws holding the nose pads down if the nose pads are too loose. The bridge of your nose holds the majority of the weight from the frame and the lenses and should wobble only slightly. If the nose pads aren't properly secured, it is possible the glasses can sit incorrectly on your face and your vision can become distorted.
Some frames do not use nose pads. Skip Step 4 if your glasses lack nose pads.