Smudgy camera lens ruining all your pictures? Don't grab for your shirttails. If you want to preserve the life of your lens and the quality of your pictures, get hip to the right way of doing things. We've listed out the proper (and the very dead wrong) tools for the job. Do you have the right gear?

While your shirt is a way more convenient tool for wiping your camera lens, a microfiber cloth is a better idea.
Here are a few other wise camera-cleaning substitutions, all of which can be found at your local camera shop.
WRONG: Canned Air or Air from Compressors
RIGHT: A Squeeze Bulb
Air compressors can drip oil on your lens, and freon-powered canned air can blast your lens and cause cracks. Something with a little less power that will still get rid of bits of dust is a squeeze bulb.
WRONG: A Coarse, Used Multi-Purpose Brush
RIGHT: A Clean, Soft-Bristled Lens Brush or Lens-Cleaning Pen
A coarse brush can scratch your lens. Opt instead for a brush with soft, fine bristles (like camel hair). Use it only for your camera lens, being very careful not to touch the virgin bristles with your oily hands.
WRONG: Your Shirt, A Tissue, Paper Towels
RIGHT: A Microfiber Cloth or One-Use Lens Tissues
Anything other than a camera-cleaning cloth or tissue is bound to leave behind fibers—making your lens possibly dirtier than before. Instead, grab a clean microfiber cloth (you can send it through the wash) and wipe your lens in concentric circles, starting from the center.
WRONG: Soapy Solutions
RIGHT: Alcohol-Based Lens Cleaner or A Huff of Your Breath
When you need a bit of moisture, don't turn to a soapy lens cleaner. It takes too long to dry, attracting even more dust in the process. Instead use a fast-drying alcohol-based cleaner (always applied first to a cloth and not directly to your lens). Or try the proven method many pro photogs stick with: Give it a good huff of breath across the lens.
via Digital Photgraphy School and NYTimes.com
MORE CAMERA LENS TRICKS & TIPS:
- DIY Tilt Shift Camera Hack
- Photography Lenses On The Cheap... If You're Risk Acceptant
- How to Breathe New Life Into an Old Telephoto Lens
- How to Remove Condensation from Inside Your Phone (or Camera Lens)
(Top Image: Flickr member kodomut licensed for use under Creative Commons)

White Enamel Flatwa...
Have all the right tools, still use my shirt tail on occasion. Sue me. (But I also have a UV filter on my lenses at all times, so if it scratches/whatever I'm just out the filter, not the lens.)
I second having a UV filter for that exact purpose.
"freon-powered canned air can blast your lens and cause cracks" ?!? Really?
I have never seen that happen... I'd like to! But I did spend 15 years selling in retail camera stores, so, what do I know...
I had a roommate who cleaned the INSIDE of her SLR with compressed air. I literally sat there with my mouth open when she told me. Never did find out if she damaged anything (my biggest fear would be freezing/blowing out the light seals).
I third the UV filter. Sometimes when your'e out and about, you just need to swipe it with a cloth quick. I generally keep a microfibre cloth in my case for that reason, though.
It's not a bad idea to get a screen protector for the screen of your DSLR too. Nothing like scratching that to ruin your day.