To start learning Glay - 空が青空であるために chords, centre your learning around these elemetal chords sequence: G, D, A, Bm, Ab, Eb, Bb, Cm, A and G. A strategic approach would be to train at 50 BPM initially, and then accelerate to the song's tempo of 100. Given the song's key of D Major, adjust the capo to align with your vocal range and chord preference.