Playing the keyboard is not as difficult as a lot of piano upstarts think. In fact, the piano is the perfect instrument for music beginners, as, unlike other instruments, its layout is straightforward and easy to understand. Plus, in contrast to instruments like the guitar, to play the keyboard doesn't require a lot of unnatural hand contortions -- at least until you get to more advanced pieces, but by then your fingers will be buff.
When learning how to play the keyboard, the basics are quite simple. Looking at the piano, there are two types of keys -- white keys and black keys. As you may already know, the musical scale consists of the letters A through G with some sharps/flats mixed in. The first important fact to learn is that the white keys represent the letters, while the black keys represent the sharps and flats.
Before going any further, you must find your piano's middle C. You will find it in the middle of the keyboard. Most pianos have the name of the company that made them printed above the keyboard. In many cases, the first letter of the name is directly above middle C. If you still can't find the middle C, consult a diagram.
When starting out, you might as well tell yourself that you're not going to touch the black keys for the first few lessons. For now, focus on the white keys, which make up the C major scale.
To play this scale, place your thumb on the middle C, with the rest of your fingers on the next four successive notes -- D, E, F, and G. Essentially, you're going to play eight notes, beginning with middle C, and ending with the C that is one octave higher.
When you play these eight notes in order, you'll notice that it sounds quite familiar. Even though you may not know it, the C major scale is something that you've probably heard hundreds of times in your life, from various sources. If you do it correctly, to play your first scale should feel pretty satisfying. This is partly because the major scale is designed to musically resolve itself in a nice way.
Piano teachers have specific ways that they recommend playing scales. My teacher, for instance, taught me the standard way of playing the C major scale upwards, which was to play the first three notes with my first three fingers, then cross my thumb under and play the rest of the scale with all five fingers. Whether or not you use this particular method is up to you; the important thing is that you find natural ways to play the scales. As your ways of playing will soon be internalized, you want to find the best ways to play the keyboard.
Once you become good at playing the C major scale with your right hand -- both up and down -- it's time to learn the same thing with your left hand. Essentially, the C major scale with your left hand is the mirror image of the one you've already learned; place your thumb on the middle C, and play all the white keys down to the next C, then go back up.
After you learn how to play the C major scale, it's time to learn chords. Soon after that, it will be time to learn some other scales. For now, though, practice the C major scale as many times as it takes to sound smooth and even. It may be boring, but once you get this down, everything else in the future will be a little easier.
Basically, when learning how to play the keyboard, mastering the piano's C major scale is the bridge toward bigger and more ambitious things. So, practice that scale until you can play it in your sleep.