ah the teacher becomes the student. Another way is to sit on the edge of your bench with your feet out in front of you, chest to your to your thighs and the DBs under your thighs behind you calves, then raise and squeeze your shoulder blades together. I do them this way if my back is buggin and it helps me keep from ducking down when I raise my arms up like I do sometimes when I am standing. Just my 2cents!!
JR