The great thing about refashioning clothes is YOU get to decide what it will look like. There is no wrong in refashioning.
I decided to take in the tops of the sleeves which would also help make the neckline smaller. I pinned where I wanted to take it in.
Sew along pin line and trim excess fabric.
There you have it! A simple sleeve refashion! The neckline is so much better and the Batman sleeves aren't as big.