Washing-up liquid, a tissue, the edge of your shirt – it's tempting to reach for the nearest thing when your glasses need a quick clean, but what's actually the best way to clean them? And what should you definitely avoid? We've got the lowdown on the best cleaning methods, with expert input from optometrist Daniel Hardiman-McCartney, clinical adviser at the College of Optometrists. Find out the recommended cleaning tips to keep your glasses and sunglasses in good condition.