Start with transfering all your dart markings from pattern onto wrong side of fabric, and marking 1/2 inches before the end of the dart tip.
Right sides together, fold dart to match your snips and to finish at the 1/2 inch marking. Pin and pencil stitchline if you so wanted
Sew and backsticth starting at top marking and workign down to snips. Backstitch and clip threads
Using a tailor’s ham or rolled towel, press seam allowance flat
The Book says: “A Cut-away Dart is used in garments that require extremely wide darts (primarly in a bodice front). A cut-away dart reduces bulk in the finished dart area. The dart is stitched like a seam and then pressed open.”