I tried this for the very first time a couple weeks ago, and wanted to share my process and the results with you.
First, I applied kiln wash to the inside of a 6 inch terra cotta pot saucer, so the melted glass wouldn't stick to it. I also put a large piece of clear glass on the bottom of the saucer; I had read somewhere that this helps keep the kiln wash from peeling off and embedding in the glass.
Next, I strung wire between two 6 inch kiln posts and laid that on top of the terra cotta saucer. If you are trying this at home, make sure you use specially made wire that is safe at high temps. I got mine at a local glass company where I get my fusible glass.
Then I layered peices of fusible glass on the wire. A key here is not to use too many dark colors; they tend to overwhelm the finished piece and leave it muddy. Also use very little black for the same reason. I used a mixture of opaque and transparent glass.
And loaded up the kiln...
The finished melts, ready to carve up into some pendants...