One more note, most of this lesson would work with any vector program. I use Adobe Illustrator CS4.
Open Illustrator. Open File>Place and choose the image you want to trace. I have the doll and clothes all in one file. The clothing is not to scale and doesn't fit the doll yet.
In Illustrator, every shape or object is its own sub-layer. This can be a bit confusing and we'll look at some examples of this. To start, get the pen tool and start tracing the doll. I create a rough outline using a stroke with no fill and straight lines. Start with large areas first.
Next up, grab the convert anchor tool from the pen menu. We're going to start changing those points and straight lines into curves.
Each shape is drawn on top of the previous shape. These fingers need to be repositioned under the hand. This can be done using the Object>Arrange>Send Backward menu, or you can use the shortcut (Command or Control - Bracket. It's the left bracket for bring forward and right bracket for send backward), or you can rearrange the sub-layers in the layers menu.