You can try and visualize this by placing a deck of cards between your hands with your thumbs pointed up and sliding your left hand away from you and your right hand towards you.

The cards near the center of the deck are not offset very much, but the cards near your hands are offset much farther.

In this example, your left hand represents the Pacific plate and your right hand represents the North American plate. The middle of the deck is where the San Andreas fault would be, and the outer cards represent how the motion between the Pacific and North American plates is accomodated on faults parallel to the San Andreas. Some of these other faults are located as far away as Nevada!