People handle icy driveways in many different ways. Some energetic homeowners break up the ice using gardening tools. This is environmentally friendly, since no other materials are being added to the mix, but it's labor intensive. Salt is commonly used to melt ice because it's soluble in water and easy to spread. But, salt has the disadvantage of promoting rust on the undercarriages of cars, and it can damage the landscaping when it mixes with the soil. Non-toxic antifreeze is easy to apply, and lowers the freezing point of water in a way similar to salt, but it doesn't have a lasting environmental impact.
Purchase a non-toxic antifreeze. The ethylene glycol component of "standard" antifreeze is extremely poisonous and its use should be avoided in situations where it can be introduced into the environment. The non-toxic products substitute propylene glycol for the ethylene glycol, thereby removing the most toxic component. These products are available at your local home improvement and hardware stores.
Prepare the driveway. Remove as much snow as possible to enable the product to work directly on the underlying coat of ice. If it's safe to move the car, park it on the street so that you can apply the antifreeze to the entire driveway. It's not necessary to chip the ice. The addition of antifreeze lowers the melting point of water, and many commercially available products are effective at melting ice at temperatures as low as -50 F, if used at full strength.
Follow the directions on the container. If the temperatures aren't bitterly cold, it may be recommended to dilute the antifreeze before applying. This will save you money and make the product last longer. Pour the mixture into a spray or shaker container and apply using even strokes. For very large areas, buy or rent a pressurized receptacle that can spray the solution over a large area in a relatively short period of time.