Us who?

 Genesis1:26NIV"Then God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals, a and over all the creatures that move along the ground.”"

 Who is the us(1st person plural) mentioned in this verse. Well the speaker is the Lord JEHOVAH so he is the principal referent but the pronoun necessarily refers to at least one other said to be in the image (Grk eikon) of JEHOVAH according to strong's eikon is a figure/copy of an original. What does that entail in the case of JEHOVAH well we note that mankind's being in the likeness of God put them above the remainder of the physical creation. So man with his mental, moral and spiritual attributes that facilitate a filial relationship with his creator is a baseline as to what it would mean for a creature to be in the image and likeness of JEHOVAH.

For further confirmation consider 

Genesis9:3,4NIV"everything that lives and moves about will be food for you. Just as I gave you the green plants, I now give you everything. 

4“But you must not eat meat that has its lifeblood still in it." 

Note the hierarchy the senseless non- living ground is not even mentioned. The plants can be used as food by man and his livestock in a sustainable way. 

Although permitted to supplement their diet with meat. There was to be no wanton slaughter of these subhuman souls . The blood of whatever animals were used as food was to be drained as a gesture of respect to the giver of all life.

Man though was on another level entirely:

 Genesis9:6NIV"“Whoever sheds human blood,

by humans shall their blood be shed;

For in the image of God

has God made mankind."

Thus no creature below the level of Mankind could be spoken of as being in the image and likeness of God. Thus we are compelled to look to the superhuman realm for a creature that can be spoken of as being like God, one who would be considered a God by humans who might encounter him. One who could consciously give a positive response to the command to make man in his image. With man as a baseline we cannot give consideration to any impersonal abstraction or force. Only a Son like man is would fit the role.

Genesis3:22NIV"And the Lord God said, “The man has now become LIKE one of us, knowing good and evil. He must not be allowed to reach out his hand and take also from the tree of life and eat, and live forever.”"

Again suggesting a privileged Son with delegated authority to make law/regulation.

After acting as JEHOVAH'S representative and executing JEHOVAH'S  judgment on mankind note the appearance of superhuman representatives of mankind's creator.

Genesis3:24NIV"After he drove the man out, he placed on the east side e of the Garden of Eden cherubim and a flaming sword flashing back and forth to guard the way to the tree of life."

Note also:

Genesis3:8NIV"Then the man and his wife heard the sound of the Lord God as he was WALKING in the garden in the cool of the day, and they hid from the Lord God among the trees of the garden. "

And:

Genesis11:5-7NIV"But the Lord came down to see the city and the tower the people were building. 6The Lord said, “If as one people speaking the same language they have begun to do this, then nothing they plan to do will be impossible for them. 7Come, let us go down and confuse their language so they will not understand each other.”"

Obviously JEHOVAH'S descent from the heavenly realm was by proxy with Superhuman messengers serving as representatives authorized to speak and act on their Lord's behalf.

Doubtless any from among these who would be invited to serve as JEHOVAH'S instrument in forming a home for man and then man himself. Would he of an exceptionally privileged station it would not be surprising at all if he were found to be the chief of these superhuman sons of JEHOVAH.