The first step is to introduce a lot of silica and shattered glass piece into the furnace and allow the glass to heat. The type of glass raw material specifically used for blowing is called cane. If available, it can also be used. Once the glass is molten and pliable, the worker uses a blow pipe to separate a bulb of it. The bulb size depends upon the type of product which has to be made. When the bubbles start to appear in the molten glass, you should know that it has melted appropriately.
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The process of free blowing follows next. In this process, puffs of air are introduced through the mouth. These air puffs form an elastic skin inside the molten bulb of glass, also called a gather. The worker can then use the air through the blow pipe and his handling skills to give the blob spooled at the end of the pipe, the desired shape. These skills are all about rotating the pipe, swinging it, and using appropriate tools to provide the desired cuts.
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After the process is done, the glass is brought to room temperature gradually. This is done so, because in case of rapid cooling cracks can appear in the produce. The whole process can take quite a bit of time. Once the glass piece has cooled to room temperature, it can be decorated.
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There are many factories that allow public display of glass blowing on specified hours in a week. If you want to learn the skill it can be a good opportunity.