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.