- 1). Heat a container of water until it boils. Make sure you have a container large enough to fit the cap of your water bottle.
- 2). Dip the cap of the water bottle in the water so it is fully submerged. Leave it submerged for a minute.
- 3). Remove the bottle from the water and check to make sure it has softened.
- 4). Unscrew the cap very slowly, applying steady pressure between the bottom part of the cap and the cap itself, to keep the two pieces connected.
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