This was written by SweetResults
The molds and bottles can be done in one day, for best results though, plan on 2 days for overnight drying of your latex mold.
Instructions for Sugar Beer Bottles
Remove label and wash the bottle you want to mold, fit a cork wrapped in plastic into the top so that it is even and flat with the top of the bottle. You may have to cut the cork to size first, then wrap in plastic and insert into the top of the bottle. If you do not use the plastic you may get bits of cork in the top of your mold. This will not harm your mold.
Using Rubber Latex (paint several coats over the entire bottle (except the bottom of course), letting it dry in between coats. It is best to let it sit over night after the final coat, but I have made and used a mold in one day.
Once it has dried thorouly begin lifting the mold from around the bottom of the bottle, loosening it all the way around.
Roll the mold off the bottle, do not worry if it begins to stick to itself a bit, it will pull apart. To roll the mold completely off the bottle it will most likely turn inside out. Simply use a mixing spoon to push it right side out. As the mold cures more over time it will stop sticking to itself.
Using any kind of modeling clay, make a half bottle mold using the same bottle, this will be the support for your latex mold. If the mold tilts the top of the bottle downwards at bit this helps, I did not think to do this when I made my first mold.
Rest the latex mold in the clay mold and then prepare your sugar.
Mix ½ cup sugar and ½ light corn syrup in a two cup glass measuring cup and place in microwave. Microwave the mixture for 6 minutes at 50%. then micro at full power for another 2-3 minutes, depending on how dark you want your bottle. It will continue to darken a bit once you remove it from the microwave.
Carefully pour the mixture into the mold a little at a time, rotating the latex mold slowly to evenly coat the mold, letting it rest in the clay mold to keep its shape. The latex will be hot to the touch, so gloves or potholders are needed. Once you have coated the mold, continue to pour the sugar into the mold and continue to rotate until you have used all the sugar.
Once the sugar has cooled, remove the mold from the sugar bottle the same way you did from the real bottle, loosen the bottom, and roll the mold off the bottle. When you get to the neck give it a gentle tug and it will come free.
I was able to make six bottles in one afternoon with only one mold. If you have any trouble with the neck of the bottle you can always wrap it in gold foil like some of the fancy imported beers!
I made my labels in Fireworks, but you could use any program like Photoshop, Word, whatever is comfortable for you. If you are not selling the cakes and do not have to worry about a copywrite you could even copy actual beer labels from a Google search and size them in any similar program.
I printed them on regular paper first to test the size. Once I was satisfied with the design I printed them onto edible sheets and cut them to size. A few seconds in the freezer and they separate easily from the backing paper and I attached them with a bit of corn syrup. If you do not have an edible printer you can always make paper labels and stick them on with corn syrup as well. Just let everyone know not to eat them!
I realize there could be some concern of latex allergies, I am not sure to what extent the latex will transfer to the sugar. If you do not want to use rubber latex for your molds these sites also have mold making materials that may work for you instead. If you use something like the Silicone Plastique I would think you could mold the plastique completely around the bottle, then once it cures cut it in half to release the bottle making 2 half bottles that could then fit back together. Band them together with rubber bands and pour the sugar into the mold, rotating to coat it. Once the sugar hardens you could then release the bottle from the 2 molds. I think I would have tried this if I had more time to order the Plastique.
I hope these make sense and at least point some of you in the right direction to start making your own bottles.