Rub! Rub her feet, rub her back, rub her shoulders.
If family members (yours or hers) offer help, take it—but be specific about what you need help with. One of the best things someone can do is bring dinner over or babysit while the new mom takes a nap during the day
Sometimes you just have to let a crying baby cry—believing you have some control will only frustrate you. The baby will pick up on that emotion and cry even more. If you’re rested, you can handle the situation much better.