The way I see it is that the word man is not referencing Adam but mankind.
"Let us make man in our image, after our likeness: and let them have dominion..." Gen. 1:26
"So God created man in his own image, in the image of God created he him; male and female created he them." Gen. 1:27
I see 4 things that make us "in the image of God"
1) A trinity of being = Body, Soul, Spirit = 3 in 1
2) Freewill just like God
3) The ability to create. Not in the sense of bringing something into being from nothing but we have been given an imagination and creative ability that allows us to produce very beautiful paintings, sculptures, art work, crafts, etc. from zero to wonder and thus be creative like God.
4) We have been given a gift of eternity. This gift allows us to live on eternally with God or (based on #2) live on eternally without God.
The only difference with Adam is that he began as an innocent being in the garden before he fell and died spiritually. From that point on we are all like Adam (after the fall) born into this world dead because of sin.
Because Christ conquered death at the cross, we can exchange our death for His life.