This experiment works best with a bottle that has relatively thin plastic. You need to be able to twist the bottle, so bottles made of thicker plastic will be difficult to use. You also want to use a standard size (16.9 oz or 500 mL) bottle or larger, not the miniature ones.  You want the bottle to be mostly empty: if you leave a small amount of water in the bottom of the bottle, you will see a cloud of water vapor form at the end.  Bottles with smaller lids also tend to work better. While this step isn’t entirely necessary, it can make it easier to twist the bottle for the experiment. Recycle the label when you’re done with the experiment. In order to build up the air pressure inside the bottle, you need to decrease the amount of space available by crushing the bottle. Start by squeezing the middle of the bottle and twist the bottom.  Starting the twist can be difficult. In some cases it can be easier if the bottle starts out slightly deflated. Remove the cap, squeeze the bottle a bit and replace the cap while keeping the bottle slightly squished. Make sure the cap is tightly screwed on to the top of the bottle before beginning this step. As you twist the bottle, you will notice it will become more difficult. Twist the bottle as many times as you can until you can’t twist it anymore. If you are not strong enough to do it, ask an adult for assistance. Keep the bottle pointed away from your face and others while you are twisting the bottle. While it is unlikely for the bottle to pop during this step, it is possible. Grasp the bottle tightly against your stomach with the cap facing away from you. Use the side of your thumb to quickly twist the cap off. Make sure you fully twist the cap off, or the cap won't pop out. If done successfully, the cap should fly across the room.  Another way to pop the cap off is to hold the bottle between your legs and then twist it with your hand. If the cap does not fly across the room, there wasn’t enough air pressure built up inside the bottle. Untwist the bottle, blow into it to refill with air, and try again. When the cap flies off you may notice that a cloud of white vapor is coming out of the bottle as well. This is water vapor that is formed when the cap gets released. As the pressure builds inside the bottle, the water molecules get squeezed together. When the cap goes off, the temperature inside the bottle cools causing the water molecules to condense into vapor. This is also how clouds form in the sky. At cooler temperatures, the water vapor forms around dust particles to condense.
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One-sentence summary -- Obtain an empty plastic bottle. Remove the label from the bottle. Squeeze the bottle in the middle and twist. Twist the bottle about 4 to 6 times. Untwist the cap with your thumb. Watch the water vapor.

Q: A standard razor will not give you detailed brows, and can be dangerous to use near your eyes. Instead purchase an eyebrow razor, whose small blade will give you the brows you desire. You can order an eyebrow razor online or purchase one at your local beauty supply store. You will get a closer shave if you apply shaving cream to the area of skin surrounding the eyebrow. Try starting with a dime-sized amount, and use more if necessary. Try applying the shaving cream when you get out of the shower. Only put shaving cream over the part of your eyebrow you want to shave. Use a cotton swab to wipe away any excess shaving cream so you can see what you're doing. Use your non-dominant hand to hold the skin around the eyebrow taut. This will help you get a closer, more detailed shave. Then use your dominant hand to begin shaping your eyebrow. It’s important that you stroke the razor in the same direction that your eyebrows grow. If you use the blade in the opposite direction, you can nick your skin and possibly create ingrown hairs. Instead, gently stroke the razor in the direction that your eyebrows grow. Also, avoid shaving above your eyebrows or they could look unnatural. You should check your progress in a mirror as much as possible. It is easy to accidentally shave off too much of your eyebrows. To prevent this from happening, step back and look in the mirror after completing each section of eyebrow. In order to maintain the look of your newly shaped eyebrows, you will want to shave them regularly. Try shaving about once a week, or more if your hair grows quickly.
A: Purchase a razor made specifically for eyebrows. Use a small amount of shaving cream. Hold your brow skin taut. Shave under your brow in the direction of hair growth. Check your progress frequently. Maintain your brow shape by shaving weekly.

Article: Most flags are either rectangular or square. Your flag doesn't have to be rectangular, but you should stick to simple shapes that are easy to see from a distance. For example, Nepal’s flag is made of two overlapping triangles.  Consider what you will be using your flag for. A triangle will work well for a pennant flat, while a rectangle will work for a sports flag. In general, rectangles are the easiest shape to work with because they give you the most space to create your design on. Some of the most common flag designs are bicolors, tricolors, and quarters, or use stripes, panels, and borders. The flag can also be a solid color with a unique symbol in the center. Alternatively, you can place a rectangle in the upper left hand corner called a canton (like on the American flag) that includes a symbol.  You could create a symmetrical flag, like Japan's flag, or an asymmetrical flag, like Norway's flag. Look at flags for other countries and sports teams to get ideas. If you really want a detailed flag, take a look at some of the state and community flags. As a general rule, you should only use 2 to 3 colors in your flag design. If you use more they can be hard to distinguish. The most common colors found on flags are black, blue, green, red, white, and yellow. You can use light and dark colors to create contrast.  You do not need to stick to the most popular colors. Instead, choose a color that symbolizes the place or organization your flag represents. Avoid colors that are too similar to each other, such as red and orange or navy and dark purple. They won't stand out as well.
Question: What is a summary of what this article is about?
Choose the shape for your flag. Choose a simple design. Use 2 to 3 colors.