One of the easiest ways to clean glasses is to use a lens-cleaning spray. First, use a microfiber cloth to wipe away any dust ...

However, one product has consistently proven its worth; Peep Club's Instant Relief Eye Spray, available for £15. I first discovered this gem when I noticed Trinny Woodall using it during a flight.

Prescription eyeglasses can cost as much as $1,000, and most have plastic lenses, which scratch more easily than glass. Clearly, you need to protect your investment. But should you clean lenses ...