To learn Jeffrey Foucault - 4&20 Blues chords, focus on the sequence of these chords: D, C, G, D, Gm, D, G, Gm and C. Start with a comfortable 61 BPM and as you become proficient, aim for the song's BPM of 122. Considering the song's key of G Minor, position your capo to suit your vocal and chord preferences.