In one sentence, describe what the following article is about: For the best fit, use a flexible tape measure like one you would find in a sewing kit.  Measure the head of the person who will be wearing the headband from the nape of the neck, up over their head where the headband will be and completing the loop back at the nape.  If the person is unavailable to be measured, you can use these general guidelines:  Preemie: 11”-12” Newborn:  13” Up to 1:  14” 1-6:  15” 7-Teen:  16.5” Adult:  17.5” Especially with babies, be sure to get a good fit that is not too tight.  Constricting an infant's head could have a problematic effect on its growth and development. Choose a fold-over elastic.  This is the preferred elastic for headbands.  It is available in a variety of colors and patterns at your local fabric store or hobby shop.  Fold-over elastic has a finished, shiny side and a matte underside, and a seam running longways down the middle.  This elastic comes in 1/8”, 3/8” and 5/8” widths.  The one most commonly use for headbands is 3/8", but some like a thin 1/8" headband, especially for babies. Some elastic is made with silicone strips in the back.  This is useful if you are concerned about the headband slipping. Measure the piece of elastic according to the measurements you took or the average length for the age of person you are creating the headband for.  If you are using actual head measurements, keep in mind that you want the headband to stretch.  Subtract one inch from the head size to make sure the headband will be snug. If the person who you are making the headband for is there, wrap the elastic around their head and make sure that the elastic stretches just enough to hold the headband in place once it is complete. Beware of making the headband so tight that it would be uncomfortable.
Summary: Measure your head. Choose your elastic. Cut the elastic to fit your head. Test your size to make sure there is some stretch in the fabric.

The most highly-recommended homes for gerbils are large fish tanks. A fish tank allows you put in plenty of bedding for them to bulldoze and burrow into without worry that they'll kick it out like they would with a wire cage. Wire cages can work in a pinch, but are not recommended for the long term.  A gerbil will chew the wires of a wire cage and this can hurt their noses and muzzles. The most important part of your gerbil's environment is room to dig, a minimum of 6 inches (15.2 cm) of substrate. So never go solely with a wire cage, as this can limit the gerbil's ability to dig and tunnel. Plastic "hamster homes", or any cages with plastic trays or components, are highly discouraged. A gerbil will easily chew through the plastic and escape. Modular systems, such as Rotastak and Habitrail, are also not recommended for any rodent. As well as causing serious health and enrichment issues, in the case of gerbils you run the risk that one of your gerbils will 'claim' a section of the tubes and this can lead to major fighting and even death. Adding a topper to your large glass tank means your gerbil will be secure in its home but the tank will still get the ventilation that it needs. If you are buying a wire topper that is not made specifically for the tank you have, just make sure that it will fit the tank securely.  Make sure the top is tight, as gerbils can jump! If you only have a topper that is a bit loose, you can make sure your cage topper is secure by placing heavy objects on the edge of the topper. Remember gerbils must be kept in pairs but you cannot introduce an adult to an adult without a split cage. A divided cage allows the gerbils to slowly acclimate to each other, otherwise they may fight and once can kill the other. Instead of dealing with a slow introduction, consider getting several gerbils at the same time that were raised as pups and litter mates.
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One-sentence summary -- Consider getting a large fish tank. Avoid plastic cages. Consider a wire topper to allow for ventilation. Buy or build a divider if you are planning on introducing two gerbils that were not raised together.

Problem: Article: Card counters are notorious for playing blackjack for hours and hours, often without eating or enjoying the amenities available at the resort. Acting like a tourist just looking for a simple good time may take the suspicion off of you. You want to blend in. Busting out your three-piece Armani suit is not what you want to do when starting your card counting career at your local casino. Leave the Italian suede at home and act like a regular Joe. Dealers are trained to shuffle the deck upon an unexplainable increase in the bet. For this reason, only up your bet in small increments and at seemingly random points in the game. This may seem counter to making money, but if you get thrown out, you'll be making zero. No, card counting isn't illegal, but it is heavily frowned upon and you can be asked to never return. This is why we had you practicing with the TV, radio, and several messy, loud-mouthed children. If you are so busy counting your lips are practically moving, it's a dead giveaway. Go ahead, get a drink, make small talk. Enjoy yourself.  Counters have a reputation for being "zoned in" to the game.  He will remain fixated on their cards while everyone else is looking at a gorgeous woman. Don't be that guy. You need to be proficient enough at counting that you can carry on a conversation.  Chat with the dealer about how their day is going.  If the pit boss comes up, chat with him, too. Many dealers know how to count cards.  A dealer that likes you will be more likely to wait before shuffling on a favorable deck and shuffle sooner on a bad one. A dealer can help you or hurt you.  Motivate the dealer to be for you. Same goes for the entire pit crew -- get them on your side, your not-so-heinous crime may slide under their radar. At any time, there are hundreds of cameras going on in the casino in addition to the eyes of the dealers, those in the pit (behind the tables), and the security staff. If they'll catch a waitress for serving a customer every 18.37 minutes, they'll definitely have the attention span to monitor you. Because of this, it's very important to be on your best behavior. If a casino suspects you're counting, they probably won't come right out and say it. They may have someone start a conversation with you to distract you, assign you a high-speed dealer, shuffle spontaneously or change the betting rules. If any of these happen, back down slowly, but immediately. When you hit a table, stay there for a spell. Why would you leave? And when you make your moves at this table, take a second to think about it. Normal blackjack players haven't spent the past three months staring at this exact set up in black and white. Everything you do needs to be nonchalant and casual. Do not jump from table to table every time the deck sours.  This will bring you to the attention of the casino personnel fast.  Make minimum bets until the deck is richer. Increase casually because you're doing well -- not because you know what's about to come.
Summary:
Act like a tourist. Let your bet ride, if you need to increase the bet. Appear to be interested in other things besides the game. Tip the dealer. Know who's watching you. Do everything slow.