Sewing Tip: When notching fabric edges for tension release, use a straight machine stitch to reinforce the edges before clipping- this reinforcement stitch is called staystitching.
If you find yourself having to sew an outward-curved edge to an opposite curve or straight edge, you'll have to add some wedge notches to outer curve so that you can comfortably and accurately align the opposite seam edges. In order to maintain the stability of the curved fabric edge and prevent it from unraveling or stretching out, it is good practice to first reinforce the fabric edge with a machine stitch. As noted above, this stabilizing stitch is called a staystitch and should be applied next to the seamline but within the seam allowance. Keep in mind that staystitching is a purely stabilizing stitch and should not be visible on the garment's face side.
Not only does staystitching provide a way to strengthen notched fabric edges, they also provide a notching guideline: As you apply your wedge or slash notches, clip up to about 1/8" away from staystitch being careful not cut directly through it.