Brewing your own soda is a whole lot easier than you might think. All you need is some sugar, bottles, flavoring, and a little time. To get started on your own batch, you'll need: Enough bottles to hold roughly a gallon of liquid. Old recycled plastic soda bottles work fine, as long as you clean them properly. Many soda-makers prefer the plastic bottles because they have less of a chance of breaking while the soda bubbles. Glass bottles, on the other hand, are more environmentally friendly and will last longer. Flip-cap glass beer bottles work great for making soda, as long as you keep an eye on them while they carbonate. Sweetener. Using regular white sugar is fine, though alternative sweeteners like honey or agave nectar are also effective if you want to cut refined sugar from the equation. You'll need about a half-cup to a cup of sugar or the equivalent in alternative sweetener, depending on how sweet you want your soda. Yeast. Commercial yeasts like champagne yeast are commonly available at groceries, natural food stores, and beer outlets, and are perfect for getting your soda bubbling. Don't use bread yeast to make soda. Flavoring. The sky's the limit when it comes to choosing flavors for your homemade soda. Soda extracts and fruit extracts are commonly available at home-brewing stores, in flavors like root beer, ginger, and fruit flavors. It's also just as easy to use whole raw ingredients to cook up your own flavors. Want to learn to make honey-lemon-ginger soda? We've got you covered. You'll need to let your cooked-up soda sit and bubble in the bottles for at least 24 hours at room temperature, which means you need to sterilize and wash them before you get started to kill any bacteria that will taint the soda. If you're using plastic bottles, soak them in a mixture of chlorinated bleach and water--1 tsp. bleach per gallon water--for at least 20 minutes. Wash the bottles thoroughly with dish soap and water to remove any traces of bleach, which will kill the yeast and hurt the carbonation process. If you don't want to use bleach, you can use a natural alternative, like Straight-A, which contains no chlorine. If you're using glass bottles, you can use the same method for plastic bottles, or simply boil them for at least 5-10 minutes to kill bacteria. The basic method of brewing soda is to cook up a sugary batch of flavored liquid, then add the activated yeast, and let it sit in bottles to carbonate. The combination of flavors will vary depending on what kind of soda you want to make, but the basic ratio should be about 2 cups of sweetener for every gallon of water you use in the soda, and 2 tablespoons (29.6ml) of extract. This will form the uncarbonated base of your soda. If you're using extracts for flavoring, bring the temperature to hot, but not boiling, about 100 or 110F (38 or 43C), and dissolve the sugar in the liquid. Add about 2 tablespoons (30ml) of your flavoring extract and allow the mixture to cool for several minutes until the temperature comes down. If you're using raw ingredients for flavoring, bring a gallon of water just to a boil in a large pot and add the sugar, stirring vigorously to dissolve it. Let it cook for a few minutes, stirring continuously, so the flavors infuse, then remove it from the heat and add the yeast. You've got a basic flavored drink, but now you've got to add the bubbles. When the sugary liquid has come down to around 100F (38C)--it needs to be warm enough to activate the yeast, but not so warm as to kill it--add about a 1/4 teaspoon of champagne yeast to the mixture and stir vigorously to activate. Yeast, depending on the age and the potency and the climate, can be a tricky thing. When you're first starting out, you may end up with soda that's too carbonated, or soda that's too flat, depending on how much you use. Anywhere from 1/4 to 1/2 teaspoon can be an appropriate amount. It's best to err on the side of not-carbonated-enough, though, since you can add bubbles after the fact. Overcarbonated soda can cause bottles to explode, which can be messy at best and dangerous at worst, especially if you're using glass bottles. For your first batch, aim for the low end of carbonated and experiment to see what works best for you. Use a sanitized funnel to pour soda directly into your sanitized bottles after adding the yeast, and cap them. Allow the bottles to sit on the counter at room temperature for at least 24 hours to carbonate fully, then put them immediately into the refrigerator. If you cooked up soda with raw ingredients, it might be appropriate to run the soda through a strainer to get out any sediment or hard bits that might be left at the bottom of the pot. If the bottles get too warm after being filled and capped, they may pop their tops or burst. As soon as they're done bubbling at room temperature, put them in the fridge to keep them safe. After letting the soda sit for 24 hours, take a bottle outside and open it. It might fizz up uncontrollably, letting you avoid a nasty mess if you're in the yard instead of the kitchen. If you're satisfied with the carbonation and the taste, put the bottles in the fridge and enjoy them over the next week or so. After five days in the fridge, they'll tend to lose some of their carbonation and become flat. If the soda isn't as bubbly as you'd like it, you can let them sit on the counter for another day or two to hopefully increase the carbonation. If that doesn't work, you can also add another tiny pinch of carbonation to each bottle, if you want, to try again. Or just enjoy the sodas slightly flat and cook up another batch!
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One-sentence summary -- Assemble the necessary ingredients and equipment. Sterilize and wash your bottles. Cook up the flavored syrup. Add the yeast. Pour soda into the bottles. Take your first taste outdoors.

Relocate them outside or somewhere else where they can receive plenty of airflow. The alcohol will soon evaporate and take the water with it, leaving your insoles clean, disinfected and smelling fresh again. Don't wear the shoes again until they've had time to dry. Doing so will just introduce new germs and moisture.
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One-sentence summary --
Set the insoles aside to dry.