Complex sentence: Charlie reminiscences about him going on a tour to California, and waking Dizzy and his wife Lorraine in the middle of the night so that he writes some music he's just improvised.
Split into simpler sentences: Charlie reminiscences about him going on a tour to California. In the next flashback we see him waking Dizzy and his wife Lorraine in the middle of the night so that he writes some music he's just improvised.