You click on "home" in the top toolbar and then select "Edit Layout" from the drop down menu. Then you should see the green border around the widgets and then a little triangular window resizer which you just move around to resize then once you accept tthe new layout it should save.

Note: If the border turns red, this means that one widget is overlapping another and so you need to resize them in a way that they all fit. I would prefer the widgets to slide out from the side of the window instead of covering the whole page all the time, but I guess Nokia wanted to go for something different and unique from all the other PDA type devices.