The Lilypad Layout is a tool available on Openprocessing.org that allows you to visualize or digitally sketch out a circuit before you begin sewing.

Personally, I'm a pencil and paper gal but this tool can be an easy way to quickly visualize a simple circuit using all the Lilypad Arduino components. I do wish it had at least a few other basic electronic components like resistors, transistors, etc. to add to the sketch.

To sketch a circuit, you drag and place components you need from the right column to the left and make "connections" by clicking and dragging from one through-hole to another.

The tool was developed by David A. Mellis.