What I did, was point to what side I wanted. I'd point right, click & treat. Then I'd point left, click & treat. Once my dog had mastered each I would point to the right, then the left, click & treat!
Then once she mastered that, I'd point right, left, right. Click & Treat!
Finally... Once she has mastered that, I stopped signaling. She was so enthusiastic and knew that something would get her the treat, so she did right and left on her own without signaling, so I clicked & treated.
The hardest part is getting away from the wall and the notes. (I trained my dog in a corner, sitting) I started right by the wall, and slowly moved away from the wall.
Hope this helps!