Sewing Tip: Choosing The Correct Armhole Finish In Dressmaking
If you find choosing a clean-finishing technique for a garment's armhole edges confusing, the first thing you should do is refer to the neckline finish. By convention, the finished armholes should either match, or work visually with the garment's neckline.
For example, if the neckline is finished with a shaped facing and features no visible topstitching on the garment's right side, it is best to clean-finish the armhole edges with a matching technique that also uses no topstitching. Conversely, if the neckline is finished with a topstitched technique such as binding, the armhole edge should also be completed using some form of topstitching in order to give the garment a visual and structural balance.