Joseph Fielding Smith writes that Jesus was the Creator in the Premortal existence under direction of God the Father.
Joseph Fielding Smith, "The Savior and Adam in the Pre-existence," Improvement Era (July 1953): 549, 550
In relation to Jesus Christ it is sufficient to say we know that he was the Creator, under the direction and commandment of his Father of this world and many other worlds. John in his introduction to his gospel said this:
"In the beginning was the Word, and the Word was with God, and the Word was God . . .
"All things were made by him; and without him was not any thing made that was made.
"In him was lie; and the life was the light of men." (John 1:1, 3-4.)
A plainer translation could be given, but this will suffice.