"Fusing glass is just what it says, fusing two or more pieces together. For glass you need a lot of heat and this can be accomplished with a kiln that is especially made for glass firing (which is easier to operate) or you can use a regular ceramic kiln, which requires more "watching" or monitoring. Also, you must be sure that the pieces of glass are compatible, but using the stencils is somewhat simplified because you are using a glass powder referred to as "frit".
To do the background I started with a round piece of clear stained glass for the base, cut another piece of compatible glass just a bit larger of the blue and layered it on top of the clear. Then I used the geese stencil (LG687) for the design. I positioned the stencil where I wanted it, stenciled some white glue to the area and finished it with a sifting of black glass powder, the material known as "frit". We moved the stencil for each placement and proceeded with the same application of the black "frit". Then it was fired in our kiln and violá!"
Here are a couple of smaller pieces that I made with Shirley and use as coasters, the tulips stencil (LL444) and the wave crest stencil (LL477):