@dfoster85 - Drinking lots of water is especially important if you are breastfeeding! You can't produce milk if you don't have enough fluid.
Taking care of yourself during the postpartum period will help your recovery, which ultimately will help you get back in shape. No point in exhausting yourself and making your recovery harder! Get all the rest you need. If you have other children at home, especially young ones, make sure that you have plenty of help with them so that you can get enough rest.
Once you are ready, you can start doing some very gentle stretches--things like neck rolls and arm circles lying on your back. I had a video by Erin O'Brien that I really liked for this period. The gentle movements helped loosen me up so that I was ready to start exercising once I got my doctor's OK.