Rashi on Numbers 5:25/רש"י על במדבר ה׳:כ״ה

1והניף THEN [THE PRIEST] SHALL WAVE [THE MEAL-OFFERING] — He moves it about horizontally and vertically, and she, too, waves it together with him, because her hand has to be above the hand of the priest (Sotah 19a).

2והקריב אתה — This refers to what is known as the הגשה — bringing it to the south-west corner of the altar before the קמיצה, “the taking off of the handful of flour”, just as is the case with all other meal-offerings (cf. Rashi on Leviticus 7:7 and Sotah 14b).