Gap showing between baseboard and shorter-pile carpet
I'm assuming that you have a similar set up that I do, I had used inside-corner shoe on my house (instead of quarter-round). In my terrible picture, I've illustrated how I had affixed my trim, running a straight length along the stair, along the riser... The corner is cut at 45 degrees... Then, I ran a piece along the wall, beveled that at 45 degrees (so it doesn't snag), and painted it to match the rest of the trim.

The red is meant to be the trim here: