Help With Animators, controllers, and sprites

I’m designing a 2d game and I have gotten stuck with using animations. I have got 1 sprite sheet right no, I will add more later, but i just want to figure this out first. I want my main character to render as just 1 sprite, its not a sheet, its just 1 frame, then use an animator so that when he walks to the right, the animation plays. I found a tutorial that uses direction, but it was from unity 4.3 and hard to follow. How do i make my 2d sprite play an animation when he walks in a certain direction?

I also have an issue with animations not playing since 5.2.2
Are you enabling the animator component when you need to have the thing animated?