1# lost is 3500 cal. 2# is 7000. so then you would aim for 7,000 burned. or a combo of eating less cal and burned cal. sorry for the confusion. this is incresed activity from what you usually do, or what your body burns at rest. cathe wrote a really good 2 part article about accutate cal counting.
you could focus on super foods like greens, beans, lentils. lots of protein,iron,fiber and other things you really need. some healthy fat is important too. almonds, olive oil, fish. lots of water! especially if you're nursing.
you might read cathe's article about how she got into shape after her kids. i think its on the blog, its an older post. intense short w/o and wt training will be your friends. quick intervals, hiit, short wt training sessions.
you could make little routines you can do in 10min, doing those when you have a spare min. also thinking about ways you can multitask. doing squats holding the baby, side lunges. doing dishes/calf raises, squats doing laundry, lunges vacumning..whatever you can think of. sometimes i just walk around the house w/ankle wts on. dont rec. if you're ankles are swollen or have bad knees. theres a ton you can do while holding them in a carrier, or you could jog/walk w/stroller. but there will be times you need a nap instead of a w/o. sleeping when they sleep is sometimes the only way to sleep.
basically finding ways to sneak it into your day. when we are so busy, if we always say i can only w/o if.....like we need to be alone for 1 hr, it wont happen often. that time is needed for so many things, prep food, cleaning, showering, sleeping, having a min to think! lol
hopefully you can find ways to destress along with reaching your goals.