As you may know when it comes to wavy things it is quite difficult to create them in Photoshop, except with Pen tool of course. In this tutorial you will learn how to use Pen tool to create a simple wave image.

Open a new window with 500x200 dimensions. Select a red color for your foreground and by selecting the pen tool start drawing a straight rectangle. But before you proceed take into account the following things:

As you can see from the image above start drawing your rectangle from Point 1 to Point 4 and then join it again to Point 1. While you are drawing this please keep the Shift button pressed, this will allow you to draw straight lines. Also before you start drawing make sure that your photoshop window is bigger than the image, so that you could point your pen tool outside the image borders.