Nick first sees Gatsby after returning from a dinner party at the Buchanan house. The disillusionment he experienced there is contrasted with the vision of Gatsby, who stands on a balcony of his mansion, gazing across the bay in a romantic (or poetic) posture.
Returning to West Egg, Nick first sees Gatsby. As Nick is about to call to him, Gatsby stretches out both arms towards the water or the green dock light opposite; Nick is mystified.
At the dinner party, Nick had been rather shocked at the drama between Tom and Daisy. He did not expect the bitter and jaded people he met and who he once knew in much different circumstances. Sighting Gatsby in a romantic and perhaps innocent pose on his balcony, Nick encounters one of the novel's great divisions - the difference between the innocent dreamer and the embittered and hollow "real" world the dreamer aspires to enter.
Though Gatbsy falls and rises in Nick's view over the course of the novel, this initial vision of Gatbsy serves as an ultimate comment upon his character. Gatsby, at bottom, remains an innocent and ambitious dreamer.
In Chapter 1, Nick Carraway joins his cousin, Daisy, for dinner at her beautiful East Egg estate. After his rather awkward visit, Nick returns to his home in the West Egg. Nick then parks his car and turns his head to see his mysterious neighbor standing still with his hands in his pockets. His neighbor, Jay Gatsby, is staring at the stars when Nick first sees him. Nick initially thinks about introducing himself to Gatsby but believes that Gatsby is content standing alone. Jay Gatsby then opens his arms towards the water in a curious manner. Nick then mentions that he thinks Gatsby is trembling as he stands with his arms open. When Nick looks out in the same direction that Gatsby is staring, Nick sees a green light shining from the dock on the opposite side of the water. Nick then looks back towards Gatsby, but Gatsby is gone.
nick first sees Gatsby when he is on his balcony and nick is outside. he is seen to be looking at a green light accross the water which we later find out is the light on the pier/dock outside the home of the Buchanans where Daisy lives