This tutorial should help you with working a knitted 3 Needle Bind Off when it’s used to join shoulder seams together for a garment. Let me know if anything is unclear or if you’d like a closer look!
I created this tutorial as part of the pattern support I offer for my Atlas Pullover knitting pattern. To check out the pattern on Ravelry, here’s the link: www.ravelry.com/patterns/library/atlas-pullover