Locate the tempo on the sheet music you want to read. Set your metronome for half the speed of the written tempo. If the original tempo is 120 beats per minute, set your metronome at 60. This will allow you to work through your piece at a slower pace until you get the hang of it.
Establish a four-beat count pattern in your head by counting "one and, two and, three and, four and." This will be the basis for the note values you count in the sheet music. If you come across a whole note, play the whole note on the one count and hold it for the two, three and four counts. If you encounter a half note, play it and hold it for two beats of the four count.
Play quarter notes and hold them for a count of "one and." This means if you have four quarter notes, you will play the first note on the first count, then the next note on the second count, the third note on the third count and the fourth note on the fourth count, holding each quarter note for the number and the word "and."
Count eighth notes on the number and the word "and." This is where a lot of beginners get confused. The notes are shorter, so beginners are often confused about how to count them. Eighth notes are counted at the same speed the rest of the music is counted. As you count "one and, two and, etc," playing an eighth note on both the number and the word "and" make it seem like the notes are faster, but in the overall context of the music, the speed is the same, only the duration changes. Sixteenth notes work the same way, except you can fit four sixteenth notes in the space of a quarter note.