How do you baby proof your bed?

I co-sleep with my 7 month old twins. Both require nursing during the night. One of them started crawling so we had to leave my king mattress which is high off the ground and we now sleep in a queen mattress on the floor. The mattress is in a small room where 3 of the 4 sides of the mattress are against a wall. But I still have the long side to baby proof. For now I’ve placed a crib mattress on its long side and a heavy desk behind to wedge it against the queen mattress. There’s still a small opening where I usually sleep with my head there and do my best to seal it off with a bolster/chair (not ideal). The mobile baby is placed away from this opening so he would have to crawl over my face to exit.

Any suggestions a for baby rail? Or suggestions in general. FTM.

Many thanks