Step 1

Firstly I need to create the sea, so to create the sea I use the pen tool to make the line. The value of the stroke is 5. The curve that I make is by using the convert anchor point tool. Than i fill it with light blue color that i selected from the swatches.After that to make the sky I use the rectangle tool and i fill it with dark blue and arrange it by sending it to backward so the it does not overlap the light blue.