Rashi on Exodus 29:35/רש"י על שמות כ״ט:ל״ה

1ועשית לאהרן ולבניו ככה AND THUS SHALT (i. e. must) THOU DO TO AARON AND HIS SONS — Scripture recites a second time in this general statement all that has been already commanded in order to impede the validity of the rites; i. e. that if they do not do this and a single thing is omitted of all that is prescribed in this section their initiation to be priests must be regarded as not having taken place and their act of sacrifice is consequently invalid (Yoma 5a).

2אתכה is the same as (another form of): אוֹתָך “thee”.

3שבעת ימים תמלא ידם SEVEN DAYS SHALT THOU CONSECRATE THEM in this manner and by means of these sacrifices on each day.