The Basics of Reading Sheet Music
There is no doubt that music theory is incredibly complicated. It takes years of study to truly understand the mechanics of classical music; then, on top of that, we have jazz theory (an entirely different enigma that I'm still trying to comprehend). Without delving into the tricky details, here are the absolute basics that you must know about music theory.
1. Understanding Musical Notation
On your music, you will find that the lines are divided up into small boxes. These are called measures. In the very first measure, you will also see a number of sharps (#) or flats (♭). These denote the key signature (see my other post about understanding key signatures!). Next to the key signature, you will see two numbers on top of each other. This is the time signature. The top number tells you the number of beats per measure and the bottom number tells you which note receives one beat (for instance, a time signature with 4 beats per measure, and the quarter note receives one beat would be 4/4).
2. Reading the Keyboard
First, let's learn how to find the note C. If you look closely, the black keys of the keyboard alternate in groups of two or three. Find a group of two, then look for the white note directly to the left of these two black keys. Congratulations, you've found the note C! After orienting yourself with this note, you can easily find the rest of the notes (ABCDEFG) by going up or down on the white keys. I'll talk about the black keys in #3.
It's also worth noting the difference between a half step and a whole step. A half step is when you go up or down to the note directly next to your first note. When we found C, we went down a half step from the black key. A whole step is equal to two half steps.
3. Notes and Rests
We hold notes and rests for a specific number of beats. If you're a beginner, just try to memorize the value of the quarter note/rest, half note/rest, and whole note/rest for now. It's a bit tedious to explain the counting for every note or rest, so here's a helpful chart that sums it all up:
(Source: Music Reading Savant, www.musicreadingsavant.com.)
Accidentals, the fancy word for sharps and flats, are key (pun unintended) to learning piano music. To find a sharp, find the note and go up a half step. For instance, C# is the black key directly to the right of C. To find a flat, find the note and go down a half step. You may have realized that C# is the same note as D♭. This may be a little confusing, having two names for a single note, but you won't even notice it after a while. Usually pieces stick to either sharps or flats alone.
Once you master these four basics, you are practically ready to start reading sheet music on your own! Find a simple piece and try determining its time signature and key signature. You can also try to sing the basic melody. Good luck!