To avoid having frayed edges, we folded the baize over every edge, added an extra crease in the overlap and stitched through all of those layers (3 layers of baize and 1 of leatherette).
The tricky bit about this project was getting the size of the baize right, since ironing creases into the edges shrinks the material around the outside. We tried to reduce this effect by ironing the baize all over before starting, and stretching out the baize before sewing the pieces together. There may be a better way of doing this, however.
Step 1: Get the materials
You'll also need some good scissors, a ruler, a measuring tape, tailor's chalk, an iron, a sewing machine and thread to match the colour of the baize.