Look at the piece of piano music you wish to convert into lettered chords. Start at the top with the treble clef, or right hand portion of the music.
Determine where the chords fall within the staff. For notes that fall on lines, begin at the bottom of the staff to convert them into letters. Each of the five lines corresponds to a letter, EGBDF, beginning from the bottom. Remember the line names with the mnemonic device, Every Good Boy Does Fine.
Repeat step 2 for notes that fall on spaces within the staff. Each space corresponds to a letter, beginning at the bottom. Remember the letters for each space with the mnemonic device, FACE, which are the letter names for each space.
Match your note to its corresponding letter and write them down. Piano chords often span more than one line or space, so you will have multiple letters for each chord.
Repeat the above steps for the bass portion or left-hand part of the music.