A general rule of thumb for origami design is that long, thin appendages should be allocated on the corners or the edges of the sheet for better efficiency. For spider subjects, most designers would choose to allocate all legs on the edges in an octagon formation, since using the corners would lead to an asymmetric layout.
Such a formation, however, tends to leave a relatively large empty space (comparing to the leg length) in the center. For spiders with larger bodies, such as tarantulas, we can still fully utilize the empty space for the body, but for slim spiders such as orb weavers, the space in the center is usually too large to be fully utilized.
To solve this problem, I looked into books on spider species, trying to find one with more features on the body so that I can fully justify the space in the center. And this particular spider soon caught my attention. It has a total of six spikes of its abdomen, a perfect choice for space utilization. The name "Micrathena" means "micro Athena", and "sagittata" means "arrow shaped".
In this design, I deliberately allocated the tips of each leg slightly off the edges of the sheet, making them strong enough to hold the body without installing steel wires. I also faithfully reflect the actual leg length differences in the design.
In retrospect, this design can still be improved quite a lot. The method I used to form the abdomen is overkill, and the last pair of spikes should be made longer (in some individuals, those spikes are really long). I also didn't make the color changing on the abdomen. I'm sure I would revise this design someday.