Applying the Folds

I've been thinking about how I would stitch the edge of the folded pieces to other fabric. I tried stretching the folds out to sew along the edge but it wasn't looking right as it flattened the edge too much. Through some playing around with the folds I've worked a way by folding a line in the opposite way to get it to stitch together. This is a big turning point in my work which means I can combine it with my tuck and work towards refining and making a product. My only concern now is how i'm to finish my fabric work so that the fabric doesn't fray.