Playing from the C position
If you took the Test Drive, you already know that you play with all fingers and thumb, and that you don't peck out a tune with your index finger. The goal of good hand placement on the keyboard is to maximize the number of notes that can be played without moving the entire hand left or right. So generally to play a sequence of notes, you want the thumb of your right hand on the lowest note in the sequence. This way you have a 5 note range within which you can play without moving your hand.
For beginner's, the simplest tunes are played only on the white keys, the naturals, because they're wider and all in the same row. Also for beginner's, the tunes first learned are in the C Major scale (if you don't remember what this is go here) which means two things: it's comprised of all white key notes and the starting (lowest) note in the scale is C (but not necessarily the lowest note in the score). If you took the Test Drive, the musical snippet there is an example of C Major and it is replicated below. And the playing of it illustrates this technique of putting your thumb on the lowest note in the sequence (C4). Because the snippet has a range of only five notes, moving the hand left or right is unnecessary.
Another goal in playing is to be able to focus on the sheet music instead of your hands on the keyboard. Of course, you probably need to initially look at your hands to ensure they're at the correct starting positions. In this example, put your right hand thumb on the C4 note key and image that it is red. Your fingers should then line up to the right of the D through G note keys. Also image that your "ring" finger's F note key is blue.
Next look up to the sheet music and visualize where your hand is by imagining it overlaying the sheet music. So in this example, you would imagine your thumb on the red C line and your "ring" finger on the blue line. Now practice playing the tune without looking at the keyboard. This beginner's tune is of course really simple. Now try the Sample Tune from the Test Drive continued page (it's also on the Downloads page).
Starting with your right thumb on the C note is what is meant by playing from the "C position". As mentioned, most beginner level tunes are in C Major and this will often be the starting position, but not always.
This visualization may be the most difficult skill you need to learn in order to play efficiently. The next step is to practice this technique with your left hand.
playing with the left hand
If you feel reasonably comfortable reading the WYSIWYP notation for the right hand, then this is easy to understand. On the other hand (arrh arrh), you'll find a lot of practice will still be required to actually do the playing.
Both of the sample tunes from the Test Drive may still be used to practice this. The only difference might be to pretend the C4 in the notation is really a C3, meaning just slide down to the next lower octave. This is the neighborhood where the left hand usually lives.
With this example it is very easy to know which notes to play with which finger. But later it gets more complicated when there is a wider range of notes and you have to move your entire hand left and right. For this reason, there is a labeling technique known as fingerings. This odd word is the numbering of your fingers and thumbs on both hands, and then marking notes on the staff to show with which to play a note. Your right hand is numbered 1 to 5 from thumb to pinky, lowest note to highest note. Your left hand is numbered the same way, but now the range is from highest note (1 is thumb) to lowest note (5 is pinky 5).
So here is an updated figure with the left hand visualization. Not much to add to this as the image tells it all. Visualize the "pinky" finger on the red C note key and the index finger on the blue F note key.
In WYSIWYP notation the number is shown behind the notehead. In order to see it, SNapp has a user preference that lets you select hollow noteheads so the fingerings can be seen. It is also recommended to change the Note Size to large. The score will then look as shown below. This version of the score includes the note tails to indicate duration.
For the next step, get this sheet music, the "Ode to Joy - snippet" from the WYSIWYP Downloads page. Follow the instructions in the previous lesson to either print it out on paper or to display it in SNapp on your handheld device. Take either to the piano. (Alternatively, you can display this web page on your handheld. However going the other routes will give you practice in the procedure.)