Then God said, “Let Us make man in Our image, according to Our likeness”...And the LORD God formed the man from the dust of the ground [human body] and breathed into his nostrils the breath of life [human spirit], and the man became a living soul. - Gen 1:26, 2:7.
Notice that man has a distinct spirit and a distinct body, but when the spirit and the body function as one entity man exists as one living soul. The living soul is the spirit and the body functioning as one man. Man himself is the living soul. The life of man (both spirit and body combined) is the living soul.
Also notice that God is the distinct Father and the distinct Son, but when the Father and the Son function as one entity God exists as one Holy Spirit. The Holy Spirit is the Father and Son functioning as one God. God Himself is the Holy Spirit. The life of God (both Father and Son combined) is the Holy Spirit.
The personhood of the Father is the Father’s own personhood, and the personhood of the Son is the Son’s own personhood, but the personhood of the Holy Spirit is the personhood of both the Father and Son functioning as one God: The earth was without form, and void; and darkness was on the face of the deep. And the Spirit of God was hovering over the face of the waters. Then God said, "Let there be light"; and there was light...Then God said, “Let Us make man in Our image, according to Our likeness” - Gen 1:2-3,26.
It is the Spirit of God, the Holy Spirit (the plural person of God) who spoke and who also created.