Rashi on Numbers 10:2/רש"י על במדבר י׳:ב׳

1עשה לך MAKE THEE etc. — make לך, “for thyself” (on thy own behalf) suggests that they shall blow them in your presence, as before a king, as it is said, (with reference to Moses) (Deuteronomy 33:5) ויהי בישרון מלך “and he was king in Jeshurun”.

2עשה לך MAKE THEE — from that which is thine own and not from the common funds (Sifrei Bamidbar 72).

3עשה לך MAKE FOR THYSELF” also suggests: you make them and use them, but no one else.

4למקרא העדה [THAT THOU MAYEST USE THEM] FOR THE CALLING OF THE ASSEMBLY — i. e. when you wish to speak to the Sanhedrin and the rest of the people and you summon them to assemble unto you, you shall summon them by the trumpets.

5ולמסע את המחנות AND FOR THE JOURNEYING OF THE CAMPS — at the time of departing on the journeys you shall blow them as a signal. Consequently you must say that they used to travel by a three-fold call: by the command of the Holy One, blessed be He, by the word of Moses (cf. Rashi on v. 18 at the end), and by the sound of the trumpets (Boraitha d’ Mlechet ha-Mishkan s. 13).

6מקשה OF BEATEN WORK — from a block of silver you shall make them by hammer blows (Sifrei Bamidbar 72).