Step 2: Test your bottle
OK, we're getting to the good part. Close the bottle with the cap and squeeze really hard.
-When you squeeze, the air pressure inside the bottle goes up, and so does the temperature.
-When you release, the air pressure inside the bottle goes back down and so does the temperature.
Squeezing the bottle was to give you a science lesson and to check for leaks. If there are no leaks, good, if there are, get a new bottle and repeat steps 1 and 2.