Unlike eye glasses, sunglasses are not fitted to our face unless they are prescription. Instead, most sunglasses are designed to fit the average face width. Sunglasses should fit snugly on your face but if your face is narrow they may not fit correctly. Loose or wide glasses can slip and fall from your face and potentially damage your glasses. Most optometrists will tighten sunglasses for little or no cost but you can also tighten the shades yourself with just a few tools.
Things You'll Need
Tighten the arms of the sunglasses. Insert a mini screwdriver into the screw hinges. Turn the screw clockwise to tighten it. As it tightens it will tighten the arms of the sunglasses.
Reposition the frame of the sunglasses. Set the sunglasses frames upside down on a level, flat surface to see if the frames sit level. If they are off-balance, pinch the corner of where the frame meets the arm with a needle-nose pliers and gently bend the frame slightly upward and downward.
Adjust the nosepads of the sunglasses. To tighten the nose pads, push your thumb against the outside of the nosepad to push them in. Make sure to apply gentle pressure to the nosepads as you bend them.
References and ResourcesGlassesCrafter: How to Adjust Glasses
YouTube: How to Adjust Eye Glasses -- How to Adjust Rimless Eyeglass Frame