Do I bind off in pattern or does it matter ? There will be a picot edge around the neck and armholes.
It does not matter since you will be picking up stitches for the picot edging.
However...because you will be picking up stitches later, you may want to do your decreases 1 or 2 stitches in from neck edge. This will give you a nice smooth edge to pick up stitches from, instead of a choppy edge.
This method is just for looks....has nothing to do with function.