Sight reading is taking a piece of music you have never seen before and playing/singing it in its entirety without stopping. The goal being, that you make very little mistakes. You need to take several things into consideration when you do this. You must recognize the notes (and their positions), watch the rhythm, look for problem spots and watch your fingering. This is a lot to try to remember when you are playing a piece that is unknown to you.
The first thing I tell students to do is to find their position on the keyboard. After they have found that, they should look at the time signature. Determine what their counting will be like. Depending on their ability, I may ask them to actually write in the counting in the music. Then, they should find the dynamic markings and look for slurs and/or staccatos. Thirdly, a student should examine the music for any problem spots. This could be as simple as finding out intervals between notes, a rhythm issue, or fingering. They should look at the music and try to determine beforehand how they will handle it. Then, keeping a steady tempo, they should attempt to play the piece without stopping.
This will develop the ease at which they play their other music. It is much easier to pick up a piece of music once you have heard it before, so if a student can plunk out the melody on a song, they will be that much further ahead when they actually play the song. As I teacher, I try to help students by playing a FEW pieces for them–on occasion. Once a student reaches a certain ability, however, it is necessary for them to “work it out on their own” instead of “parroting,” the song (what they heard played.) They can now figure it out for themselves.
Some students are working out of a book called “Line – A- Day” sight reading by Bastien. It is an excellent book to start out with. They are leveled for the ability of the student and it takes a line of music to attempt to sight read each day, using the rules I mentioned above.
When students keep up their sight reading, they will be comfortable looking at new pieces instead of being intimidated.