Alter the chord progression of the song you want to play as a flamenco number. Many songs use the first, fifth and sixth degrees of the music scale as the foundation. Try altering the progression to incorporate the first, seventh, sixth and fifth position chords in the scale. This sets up a descending order for the chord progression, which is a primary feature of Spanish guitar progressions.
Alter major chords to seventh chords by adding the seventh note related to the key of the song you are arranging in flamenco style. Keep minor chords as they are or add the seventh or ninth note of the key you are arranging in. These chords will help produce a distinct flamenco sound.
Play with your fingers. Sweeping with your fingers will give the song a flamenco sound. Use your thumb to play the lowest note of each chord and the rest of your fingers to pick the individual strings from the thinnest to the thickest. This is the familiar sound of a Spanish flamenco song and, when combined with the change in chords and progression, will give any song you play a flamenco sound.