There is a method to speed-learn sight reading of pitch notation and some claim it takes between
15 minutes to an hour per clef to learn. The steps are (bass clef and left hand training as example):
1. Put a sticker (e.g. strip of red post it) on the middle c on a keyboard
2. Put 5 stickers (e.g. strips of green) on keyboard keys that correspond to notes falling on staff lines in bass clef. Like this:
3. Configure this online
Sight Reading App like this:
4. Follow the online trainer. You only play notes that falls on a staff line (i.e. marked with a sticker on a keyboard) and skip for now the notes in between.
5. Some useful tips:
- As first training step, mentally and visually memorize the note that's on the middle staff line (first note in the screenshot above and the middle of the clef stickers) and use it as a compass for notes above and below. Some people use a separate color sticker to mark it
- Concentrate first on the notes that fall on the staff lines (skip the rest) for first practice run
- Add the notes that are between the staff lines when you're feel you're ready
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This is very fast and very simple, all it does is train visual-muscle coordination and rapid memorization. The method for treble clef (right hand) is exactly the same.
You decide when you're ready to move to extra staff lines and accidentals and you do that using the configure button and changing the lower and upper pitch limits.
Once you're good in each hand separately you combine them, and boom - you have full range of chords at your disposal.
Hope it helps!