TMI ALERT

If you're taking it for the fiber, you only need to take enough to have stool that's neither too dry or moist. Generally it should pass all in one shot, it should be easy to evacuate with a bare minimum amount of pushing, be somewhat soft, and be very easy to clean up after with no sticky residue. It may also smell like burnt asphalt when you first start adding fiber to your diet. If you look at it for some reason, it should look like the surface is somewhat shredded. This is healthy, and is exactly what you want when you do your business in the woods.