Except for the expulsion of a little moisture from their paw pads, dogs don't sweat to cool down the way people do. Sizzling summer weather makes them vulnerable to life-threatening heat stroke and dehydration. Products to help your dog chill out are available at pet stores, but you can make your own for little or no money by using things you may have around the house.
DIY Cooling Pad for Dogs
Your cooling pad will consist of a coolant layer sandwiched between two layers of foam and enclosed in a fabric cover. A pillowcase works nicely for small dogs; for larger dogs, you can repurpose bedding or a sleeping bag and cut it to the desired size. A sewing machine is useful but not essential for attaching layers of fabric -- a sturdy hand-stitched seam, snaps or fabric adhesive are all acceptable alternatives. Cut two pieces of medium density foam about an inch thick and insert them into your fabric envelope. The cooling pad should lie flat, like a mattress -- curled-up edges mean that the foam needs a further trim. Slide the coolants between the foam layers, secure the opening with snaps or Velcro, and you've got an easily laundered cooling pad suitable for indoor or outdoor use. When used outside, be sure to put it in a shady spot.
Refrigerant-filled ice packs are available in many shapes and sizes, including flexible blankets. After freezing, the gel inside thaws much more slowly than ice, thereby cooling everything in its immediate proximity for a longer duration. However, if you use ice packs that attract condensation, you'll need to take steps to prevent fabric from becoming soggy by wrapping them in plastic bags or foil. Using either condensation-proof "no sweat" coolants or old-fashioned hot water bottles eliminates the need for waterproof coverings. When hot water bottles are filled with ordinary tap water and frozen, their natural rubber or PVC exteriors deflect condensation while resisting equalization between the cold inner and hot ambient temperatures.
Making a Cooling Vest
A vest with side pockets to hold coolants against your dog's body is another hedge against overheating. The size and shape of your dog will influence your choice of style. Cargo pants have ready-made pockets perfect for holding ice packs and easily can be repurposed to fashion vests for larger dogs. If you don't have an old pair, check a thrift shop. You don't need to purchase a sewing pattern to make a dog's vest -- many are available free on sewing websites. To make a rough template of your own, lay a sheet of newspaper over your dog's back and trace the outline of the vest in felt pen, leaving generous seam allowances. You can fine-tune the fit after the fabric is cut so too much is preferable to too little.
Creating a Cooling Necktie
Nontoxic polymer water-absorbing crystals that expand and turn into gel after being soaked in water are available in craft stores. When the gel is encased in cotton, the fabric absorbs the water, creating a cooling effect as it gradually evaporates. To make a simple version, cut two strips of cotton in a length and width appropriate for the size of your dog's neck. Stitch them, right sides together, leaving one end of the tube open. Turn this fabric tube right side out. Add the quantity recommended by the manufacturer and stitch the final end closed with the crystals inside the defined area. Soak it until the gel is fully saturated and tie it around your dog's neck. While the crystals are pet safe, be sure your pooch doesn't snack on the tie.