You don't need 2 hands, you just need to have your straps set up properly, most people like to tuck the loose end back in the buckle. Don't do this, it prevents you from being able to adjust while riding and you lose foot retention because of it.
Set up your strap like this, whenever you need to loosen the strap just reach down and push the top of the buckle, if you want to tighten back up just pull on the strap.
But the best thing to do is get a clipless set up, I was hesitant at first, but eventually found a really good deal on some pedals and shoes. It's soooo much better than cages, I had them on my FG because it was my only bike, but I got a new geared bike and switched them over that that and put the cages back on my FG. The difference in foot retention is unbelievable, I hate riding with cages now.