You just use the clean water to wash the revo sunglasses. You could use the fingers to rub it at the lenses. Then you just find the clean cloth to dry it. The revo sunglasses will be cleaned. In order to protect it well, you should just put the sunglasses into the box when you don't use it. Or else, it will get dirty from the dust.
The first step is washing your lenses with warm water and mild soap. This will remove dirt, grime and oils. Then you need to dry the lenses with a specific lenses cloth, and cotton works well. Do not use paper towels or similar wipes as these can actually cause damage to the lenses. Professional lenses cloths are designed to remove dirt, smudges or fingerprints and are available quite cheaply - they are always a good choice. You should be careful, and do not touch the lenses, do not rub too hard on the lenses. Lenses cloths should be treated carefully after use and cleaned regularly with a mild soap.
Well, it seems that your sunglasses are quite dirty now. As a matter of fact, sunglasses are quite special and fragile in some way, so you have to take good care of it. I suggest that you flush the lenses after applying some detergent to them, and try to avoid rubbing the lenses with coarse cloth, for that would scratch your lenses. Afterwards, just let it dry itself. Hope you find this useful.