A homemade de-icing solution using isopropyl alcohol is highly effective. Mix two parts 70% isopropyl alcohol with one part water in a spray bottle. Spray liberally on the windshield to weaken the ice structure, turning it into a slushy consistency for easy removal. Avoid salt-based mixtures, as they can corrode your car's paint and trim. Regular rinsing of your vehicle during winter can help maintain its finish.