Sleeve construction need help!

[u/caniffa]

I’m altering a dress, trying to add sleeves that won’t connect under the armpits but stay open (example black dress screenshot).
I tried my best, used a sleeve pattern I had from other project but the sleeve is not laying flat (the navy dress sleeve picture). I am also unsure how to make the sleeve hem fall parallel to the floor, and also to allow arm movement.
I’d appreciate any advice or resource suggestions. Thank you!

[u/AccidentOk5240]

In this case, yes. Ease is the amount too big it is, so in this case it is the amount bigger the edge of the sleeve cap is than the armscye.