|This might be common knowledge. I looked for this tip in the boards and the Tips section, but couldnt find it. So, I'm posting it here for beginners. I learnt this from one of Sandra Betzina's book. This technique is used to apply bias binding.
When you apply bias binding to the armholes of a vest or a sleeveless top or sleeveless dress, keep the armhole(A) of the bodice near the feed dogs and binding (B) on top. This makes the armhole slightly smaller drawing the binding in at the armhole for a better fit.
Similarly, when applying the bias binding to the neckline, keep the binding (B) near the feed dogs and the neckline(N) of the bodice on top. This prevents the edges of the finished neckline from curling in.
Sicne it is confusing to remember what goes where, I remember it using one fo the memory techniques I learnt. Since the alphabet A comes before B, Armhole goes first and then Binding goes on top. Similarly, B comes before N, so Binding goes first and then the neckline goes on top.