You must always keep your eyeglasses clean for a clear vision. As you wear it outside, it is very easy for the glass to catch dirt and oils from outside. Also as you use your eyeglasses casually, they pick up fingerprints which may distort the vision.
The sole purpose of cleaning your eyeglasses is to remove the residue or dirt without affecting the lenses. Different types of glasses require different handling. When you buy your eyeglasses you must ask about the ways to take care of them. If you don't take proper care of your glasses then they will not provide you a clear vision thereby increasing the eyestrain. Special lens wipes are available in big retails shops and malls for cleaning the glasses. You can use these wipes for any lenses like glass or plastic. They have specific usage instructions and you read them before cleaning your glass with lens wipes. The lens wipes clear the dirt from your glasses without damaging them.
You can clean your glass by washing it under warm water. First remove the dirt by rubbing with a fine silk cloth. Then rinse the glass with warm water. After that apply a mild detergent in your hands and make circular motion in the lenses to remove the oils and residue. Rinse again with warm water. When all the dust is cleared the water will be repelled by the lens and you can dry the glass with a soft cotton cloth. You must wipe the entire moisture in the lens and the frames to keep your glass clean and durable.
For cleaning the nose pads of your glass you can use baby tooth brushes or special brushes for cleaning nose pads. You must not let the brush rub the lens as its bristles may scratch your lens. If your glass has any special coating you have to check with the optometrist for the cleaning process. If you engage wrong cleaning process then it may spoil your glass.
While removing the glass, use both the hands so that frame does not bend.
When you are not using the glass keep it in a hard case specially meant for keeping your glass. When you have designer glasses then you have to be more careful as they are expensive. Your glass will stay new and fresh as long you take proper care. Also you need to maintain the glasses clean for a clear distortion free vision.