Pitching is harder than it looks. First, you need to be able to throw the ball. Both feet are on the rubber. Then, your front foot (opposite your pitching hand, i.e. left leg for righties) goes about a foot's distance away from the rubber, on the same line as it. After, your other foot goes in the hollow right in fron of the rubber. Some fields might not have this, and if it doesn't have that dug-out space, it must be a pretty nicely kept field. Anyway, so you plant that back foot, raise your front leg in a upside down L shape, then start throwing the ball while the front foot drives forward. Try pointing your glove hand at the location you're throwing at, then tuck it into the crick of your shoulder- it might be too much to remember. In your follow through, you should be facing home plate.
The first pitch you should learn to throw well is the 4-seam fastball. This is the pitch that is usually your hardest, and the one that goes straight. To grip it, take your first 2 fingers, space them about 3/4 to an inch away from each other, and put them so they are perpendicular to a seam. Hard to understand without pictures. http://en.wikipedia.org/wiki/Four-seam_fastball