The main tool in design is the Draw Tool or Pen. It is at the end of the Shapes drop-down menu or under the Insert > Shape > Draw a Shape menu.
To draw a shape, click once and then click several times more. Drag the mouse around the new dot to make the line curving.
Eyebrows, mouth and sun rays are all two-click curved lines. Line colour and thickness can be changed in Graphic Inspector. To curve the lines, drag around the 'propeller' — a curving handle that the line shows when you click on a red dot, its editing point. Editing points appear when you make the line (and other shapes) editable. That's why you should drag the mouse around when clicking.
To rotate sunrays, press Command and drag the white square handle of the line.
Rosy 'cheeks' are ovals with Advanced Gradient colour fill. Remove outline. Choose it in Graphic Inspector, click on the 'Ripples' fill and find a combination of three or four colours, from bright red to pink to yellow, that blends with the rest of the sun's 'face.'
The background music is by Dan-O from Danosongs.com.
Read more in my new book 'iWork for Mac OSX Cookbook' (2012), follow me on Twitter at iworkinpages, like my page I Work in Pages on Facebook and add me to your circles on Google+