Step 3: Design - aesthetic
When designing your tree just remember:
1. It has to be an electrical circuit (see previous step), and so try and visualise the path the electricity takes.
2. Try not to make the distance between connected LEDs any more than twice the distance of the LED's leads, or you'll need to use extra wire (complicated)
If you look at the design B, you can see that there are two paths between the two terminals. The wires on the underside of the lowest green LEDs only connect to one terminal, and bypass them on the way around the outline of the tree. The other terminals of the lowest green LEDs are connected through the resistor, making two parallel circuits.