Hey Jazmic!
I had a similar situation in my previous set up. I made a long " rope" type thing from bright coloured material that I could stretch across the room and the kids would stay on the other side while I made lunch. Since it was not to keep them from falling down stairs it didn't have to be a secure barrier...just a visual reminder. I attached it to the wall with Velcro strips so was easy to remove or hide after daycare hours!!