Usually I make 3 copies of the birth plans. One copy for my O.B., one for the maternity coordinator at the hospital, and a copy for myself.
In the past, I would take the copy for my O.B. along during a prenatal appointment when I was around 7 1/2- 8 months pregnant. My doctor and I would discuss what was on the birth plan. I'd also find out if there was anything that I was asking for that was unreasonable and then I could make changes if I needed to. With this pregnancy, I didn't take a copy to my O.B. since everything on my birth plan had already been approved by him during my last c-section. Any questions I've had (regarding video taping the birth, holding the baby soon after birth, ect.), I've been able to bring up during previous appointments, so there really wasn't a need to go over the birth plan again.
Around 32-34 weeks pregnant, I have an appointment with the maternity coordinator at the hospital I plan to deliver at. At that time, I take my birth plan with me and go over it with the maternity coordinator. Along with signing all the consent or (non-consent) forms, we go over the birth plan and the coordinator takes notes and places them at the front of my chart. She also will inform me which things may or may not be doable on my birth plan, and sometimes makes suggestions.
As for the copy for myself, I just hold on to it so I can remember what I plan to fight for. The morning I go in for my c-section, there should be a chance to speak with the nurses who will care for my baby and myself, as well as the anesthesiologist and my O.B.. During this time I again bring up my preferences for the birth. We also go over any problems that I had during the previous c-sections.