Becoming a parent is a developmental milestone most of us hadn't expected -- it's the next step in our OWN growth process. So while your baby is getting his diapers changed and learning to roll over, you're learning new boundaries and a forming a new identity with your family members. They have to get used to your new role too -- before, they were the most "senior" generation. Now you've taken a step up -- and they need to make room.
Being a parent isn't just about taking care of the baby. It's also about the mindset of being 100% responsible for a new little life -- and all the hopes, fears, joys, and rewards that go along with it. Eventually, that will include setting up new ways of relating to your in-laws. Hopefully you can hang on to her willingness to help, without getting upset about her criticisms. (And if you want her to learn better ways of interacting with your baby, perhaps watching you do it will help her learn. I don't know many mothers-in-law who enjoy taking parenting advice from their daughters-in-law! A subtle approach usually works best.)
This takes time, though. Many parents (myself included) take months -- if not years -- to settle into our new identity as parents. Once you're more comfortable in your role, it will be easier to take over from your mother-in-law when you feel she's being overbearing. For now, though, discuss your childcare needs with your husband, and decide what you'd like your mother-in-law's role to be. Perhaps she can help out for an hour or two in the afternoons, then you can take the baby home and make dinner.
Whatever you two decide it should be, discuss it with her, in a positive way (and let your husband take the lead). Perhaps he can say, "Mom, it would be great if you could help out with the baby in the afternoons, and we'll take him the rest of the day." If she complains or criticizes, stay positive to keep family relationships strong, but stick to your guns. "Thanks for the advice, but his pediatrician suggests we do it this way." Or, simply, "Thanks for the advice." Then keep on doing it YOUR way. Over time, everyone will adjust to the big impact your little baby has on the family.