Flat-felled Split Seam

Reference: Lapped flat-felled split side seam, Handmade By Carolyn.

1. Add a rectangular tab to the dominant pattern piece (e.g. on the front piece if felling towards the back). The tab should start a tad above the top of the split. A half inch width is plenty (trim later).
2. Sew WSF stopping at the top of the tab. Snip the non-dominant seam allowance to begin finishing its split and to start trimming in preparation for felling.
3. Fell the seam. When reaching the split, continue the fold, folding the tab under to finish the other half of the split.
4. Finish as necessary, adding a bar tack at the top of the split.