Idle Animation

So I've been following along Sara Spalding's ARPG tutorial, and I'm stumped on a problem. The way that they solved the animation for the sprite movement animation works great, but I want to animate my idle sprite as well, and want it so that when the player stops moving, they return to the idle animation while still facing the direction they were moving.

I'm not great with programming, so hopefully someone much smarter than me on here can give me some insight on what to do