I don't often precum very much at all sadly. However, I discovered a technique on Jackinworld.com that makes me precum like maddness.
You only use your thumb and either your middle finger or index finger. If you are circumsized your thumb should be on the top of your penis just below the head, and your index (or middle) finger is placed on the bottom just below the head. Using only the index (or middle) finger, rub the bit of skin beneath the head on the underside of your penis is steady circular motions. Keep the circle motion going in the same direction the entire time. If you do have a foreskin, you can still do this in the same manner with the foreskin pull over the glans.
it takes damn near forever for me to get off when I do this, I precum insanely, and when I finally do get off it's amazing ... and I never even touch the glans.
If anyone tries it lemmie know how it works for you, especially if your someone like me that does not precum much. Reguardless, it's a totally intresting experience.
Now i'm hungry for precum damnit!