Originally Posted by Emrys
A lighter would be too hard to control. Plus those edges will be blackened, hopefully they won't end up showing. I used a soldering iron to cut/melt the visible edges on my Neptune skirt, but I would only recommend the hot pen method if you have a steady hand, lots of patience, and only for dark synthetic fabric.
I've read that pinking shears work well to stop fraying (cuts zigzag snips along the edges) though I haven't tried that method yet myself.
Before you start sewing all your pieces together you can run a zigzag stitch (or zigzag cross stitch with a straight line on one or both sides) along the edge of your fabric. If you look at finished clothing all the seams are finished like that as well.
I used pinking shears on my Moon skirt and it was perfect. They can be a bit of a cost, so I dont usually suggest them for people.