I am planning a homebirth myself, so haven't done it yet, but I have heard that you put a shower curtain down on the bed to protect it. I think that I am envisoning giving birth partly due to a subconscious desire to keep the mess contained! I just switched to a midwife to do a hb and will have my first prenatal with her tomorrow, so I think that I might get a better idea of things like mess, etc as we continue to meet.