To make this easy yet spectacular wall art first of all on a white paper you have to draw or print a template of a heart with 3 lines, each one perpendicular to the other or in easy words draw an H. After that cut different sized heart shapes from colored paper and fold them in half. Glue every half of the folded hearts in a way that they become the petals of a flower. Repeat the same steps for smaller flowers and fill the heart template.
You can use the same technique to make a tree too as shown. Happy crafting!