Download or purchase a diagram of the piano keys that is labeled with names of the notes. Notice that the black keys go up by two, then three consistently. Middle C is the basic starting point for piano.
Look at your diagram of the piano keys and the keys in front of you. Find middle C. Rip off a small piece of masking tape and tape it to middle C. Write "C" on the piece of tape.
From middle C, go up only white keys, marking them with pieces of masking tape and the letter name of the key. For example, after middle C, D, E,F, G. At G, start over at the beginning of the alphabet with A, B, C, D and so on. Mark each key with masking tape and its corresponding letter.
Take out your beginner's sheet music and mark the lines with the letter names of notes. Study the lines and spaces on the page, and match them up to their letters on the actual keyboard.
The first scale you will learn is the C major scale, which is the only scale that doesn't use any black keys. Download or purchase sheet music with a labeled "C" major scale. "C" notes always are just before two black keys. Make sure you know what middle "C" looks like on the keyboard and in the upper and lower staffs on your sheet music.
All major scales are eight notes. The C Major scale is C, D, E, F, G, A, B, C. To play the scale, sit down at the piano, and sit up straight. Place your right hand with your wrist raised, your thumb on middle "C" and your other fingers one on each key. Press down each key C,D, E, F, G hard enough to make a sound. When you're out of fingers, cross your hand over to the A key, starting again with your thumb until the final "C" note. Practice these motions until they are fluid.
Do the same exercise with your left hand, but beginning with your pinky finger on middle C, then pressing down D, E, F,G with your remaining fingers and crossing over and starting again with your pinky finger on the A key. Continue until the final C key. Practice the scale with your left hand until fluid. When practicing your scales, visualize the notes on the staff and say the letter names of notes to yourself. This helps you memorize notes and their location on the keyboard and the staff.
When you can play the scale fluidly with both hands, move your left hand eight white keys to the left and practice playing the scale simultaneously with both hands. Practice until the movements are fluid, and your are able to play the scales at the same time without pausing or stopping. As you progress into playing more complicated songs, simultaneous C scales are a great warm-up exercise and can be done slowly and quickly at the beginning of lessons or practice.
Learning timing is as easy as learning to count. Beginners should start with 4/4 time, which means four beats per bar (the little vertical lines that seperate each measure). In 4/4 time, a whole note, the note that looks like an "o" gets four even counts of one, two, three, four. A half note, or the note that looks like an "o" with a stick attached to it, gets two even beats, one, two. A quarter note, or the note that looks like solid black "o" with a stick, gets one beat.
Practice your C scales with each hand with all the notes as whole notes, one, two, three, four beats, for each note. Then with all the notes as half notes, one, two, each note, and then with all the notes as quarter notes, one beat each. Then, practice with a combination of whole, half and quarter notes.
Now that you know your notes, and your basic timing, you can learn simple sheet music in 4/4 time, with no sharps or flats. Purchase or download a simple piece of sheet music that includes finger placement. Practice a song until you are able to play it with no mistakes. You can now play piano.