How to Create an envelope icon in Illustrator

From task tutorial.com that how to create an envelope icon on illustrator. First draw a rectangle change the angle to 90 degrees then select gray color, select pen tool draw a shape and then go to layer select duplicate then rotate the shape using left mouse button by selecting the rotate tool. Now using down arrow key move the shape to down ,choose select tool and resize the shape then select the path go to gradient and change it angle to 90 degrees. Finally select the layer and go to effects choose drop shadow and edit opacity to 40 then an envelope cover icon is ready.