Rashi on Deuteronomy 26:10/רש"י על דברים כ״ו:י׳

1והנחתו AND THOU SHALT PLACE IT [BEFORE THE LORD THY GOD] — This tells us that he takes it after the priest has waved it, and holds it in his hand whilst he makes the declaration, and then again waves it (Sukkah 47b; cf. Sifrei Devarim 301:33).