Neat edges

How do I make neat edges for seams on reverse stocking stitch?

Hi and welcome to KnittingHelp!
You can slip the first stitch of every row for a neater edge. It works the same way for both stockinette and reverse stockinette since one is just the opposite side of the other.
Here a nice tutorial from Liat Gat:

If the edges are going to be hidden in a seam I don’t slip the edge sts but that’s a matter of personal preference.