Take any bag with a hole in it that needs to be sealed (i.e. a bag of rice). Simply seal the bag and minimize the amount of air in the bag by squeezing the empty part of the bag.
Step 2: Step 2: Cut Bottle
(CAUTION: Be careful with the knife as you may accidentally cut yourself!) Next, take an empty plastic bottle, preferably a water bottle, and lay it on its side. Take a knife and cut the bottle where it starts to even out from the lid to the side all the way around until the bottle is in two separate pieces, the cone-like top and the cylinder with no top.
Step 3: Step 3: Twist and Twirl
Next grab the bag and twist and twirl the empty part until it is tight and string-like. It doesn't matter how long the excess bag is just make sure it is sealed tight.
Step 4: Step 4: Insert Bottle Top
With the twisted bag in one hand, take the cone shaped bottle top and insert it, top facing up, along the twisted part of the bag. Simply pull the twisted part of the bag through the bottle for full security.
Step 5: Step 5: Un-spin Bag
Next you must un-spin the twisted part of the bag and pull the bag back down and over the cone. It is done correctly if the bag looks upside down.
Step 6: Step 6: Close the Lid
Finally, all you must do to seal the bag is simply take the bottle cap and tightly close the bottle. If all steps were done correctly, you will have created your homemade Ziploc bag using a plastic bottle that will not spill out.