Summarize the following:
Just a regular cooler is fine, like the one you use to keep food and drinks cool for a picnic, but it must be small enough to fit in your freezer. The cooler will insulate your ice cubes, forcing them to freeze slowly from the top down. Do not close the cooler. If you can, use trays that make larger ice cubes, or get a series of small, rectangular plastic or silicone containers. Proponents of this method claim tap water works as well as distilled and boiled water. This water will seal off your ice cubes, keeping cold air from freezing the sides or bottom. Make sure your freezer is not set too cold17-25F (-3 -8C) should do it. Leave the cooler for 24 hours. The ice should have a thin cloudy layer at the top but be clear the rest of the way through. You now have large, solidly crystal ice cubes.
Get a small cooler. Place your ice tray, mold or other freezing container at the bottom of the cooler. Fill your tray or molds with water. Pour water into the bottom of the cooler, filling in around your ice tray or molds. Place the cooler with the lid off in your freezer. Take out your cooler and carefully remove the block of ice with your ice tray or molds frozen in it. Chip away the ice around your tray or molds and remove your ice cubes. Leave them out for a minute to let the top cloudy later melt off.