If you freeze the bottle with the cap off, or carefully remove the cap, then you can try dropping a piece of ice into the water to instantly change it to ice. You can also pour the water over ice and make yourself ice sculptures.
Bottled water Boiled water Filtered water
Refrain from opening your freezer too often. Every time you open the freezer door, cold air escapes, increasing the temperature inside of it. If you really need to check it periodically, avoid doing so for one hour intervals.
Don’t use porcelain cups or hard bottles. Water expands as it freezes, so if you use a mug or Nalgene bottle to freeze water in, then it is possible that it will crack the container. A metal cup, ice cube tray, or a plastic disposable water bottle are all good options. If you boil water before freezing it, the ice will come out crystal clear instead of cloudy. There are several molds you can find online that will let you freeze ice into different shapes, such as a fish, skull, or even a shot glass.
