PEN TOOL

In order to make a perfect rectangle in illustrator  we must use the pen tool to first draw a line. After drawing the initial line find the anchor and draw three more lines until the rectangle is complete. 

You create a curve by adding an anchor point where a curve changes direction, and dragging the direction lines that shape the curve. The length and slope of the direction lines determine the shape of the curve.

In order to draw an arrow just draw a straight line with the pen tool. Open up the stroke window by going to Windows----->Stroke, then select the arrowhead that you want.

Position the Pen tool where you want the curve to begin, and hold down the mouse button.The first anchor point appears,and the Pen tool pointer changes to an arrowhead. 

In order to create a 3pt. curved line we position the Pen tool where we want the curve to begin, and hold down the mouse button. Once it's curved go to Windows----->Stroke, then under the arrow head option you can find all sorts of "arrowheads" select the one of your choosing.