Rolling side to side slowly when changing, helping her slowly transition up and down from sitting to lying down and back up again on changing table, encouraging
reaching for toys when on hands and knees so that one hand is off the ground
without collapsing, playing «row row row your boat» on your lap moving side to side and having her hold those tricky sideways positions are some examples of things you can do during the day to help her get used to lateral weight shifts.