Never wipe your lenses dry on your shirt, always rinse them under warm water first then dry them with a soft, clean 100% cotton cloth. An old t-shirt works well for this just cut it up into several small squares and you can keep one at work, home, school, etc. You may use a mild liquid detergent like Joy or Dawn if you like.
Avoid using paper towel and tissue. Prolonged use can put fine scratches on your lenses; however, if a tissue is all you have at the time using it once or twice will not hurt. Also, breathing on your lenses is not good enough. You still must rinse them in order wash all the dirt off. If you do not then you are just grinding the dirt into the lens and scratching it. Just like you should not wipe a dusty car because you scratch the paint the same applies to your lenses.
If you like you can get a spray bottle and fill it with 50% Rubbing alcohol and 50% water and spray the glasses until it drips off then wipe it with your cloth. This works best on non-glare coatings (AR) because it removes the fingerprints and other oils.