I agree with using a camera to help you keep things straight. I always take lots of pics of my blocks when i'm assembling them. For me, it easier than a numbering system.
Working with corduroy. That's always a challenge. First be aware that corduroy has nap that will look different when it runs different ways. This may or may not matter to you. I've never pieced with corduroy and have no idea what seam allowance will work. I can tell you that it pills a lot and you'll probably have to clean at least the bobbin area of the machine more than you usually would.