A Web of Intrigue

A single thread, which forms the basis of the structure which forms a span between two points. To establish this bridge, the spider finds a suitable starting point and releases a length of thread into the wind. Hopefully, this thread will attatch to another point. When the spider feels that the thread has caught onto something, it cinches up the silk and attaches the thread to the starting point.
It walks across the thread, releasing a looser thread below the first one. It attaches this thread on both ends and climbs to its center. The looser strand sags downward, forming a V-shape. The spider lowers itself from this point, to form a Y-shape. This forms the core support structure of the web.
As it walks along the initial structural threads, it lays more frame threads between various anchor points. Then it starts laying out radius threads from the center of the web to the frames. The spider does not coat the frame and radius threads with sticky material, since it needs to walk across them to get around the web.
After building all the radius threads, the spider lays more nonstick silk to form an auxiliary spiral, extending from the center of the web to the outer edge of the web. The spider then spirals in on the web, laying out sticky thread and using the auxiliary spiral as a reference. The spider eats up the auxiliary spiral as it lays out the sticky spiral, resulting in a web with non-sticky radius threads, for getting around, and a sticky spiral for catching insects.