Draw your horizon line about 1/4 up from the bottom edge of your paper.
Then, draw Your buildings.
Lightly draw a line to mark the back edge of your buildings.
Draw your diagonals from the corner to the back edge mark.
Draw straight down from the intersection of your diagonals and your back edge to the horizon line.
Erase extra marks.
Put your name on the back of your paper and work on code.org or typing.