These commandments conveyed by God to Moses concern the "tzitzit", the fringes worn by men. Why does this pertain only to men? In these passages it says "speak to the children of Israel", not "speak to the men among the children of Israel."
Numbers 15:37 - And the Lord spake unto Moses, saying,
Numbers 15:38 - Speak unto the children of Israel, and bid them that they make them fringes in the borders of their garments throughout their generations, and that they put upon the fringe of the borders a ribband of blue:
Numbers 15:39 - And it shall be unto you for a fringe, that ye may look upon it, and remember all the commandments of the Lord, and do them ; and that ye seek not after your own heart and your own eyes...