Separate the four parts
Know what belongs in Title, Lyrics, Style, and Exclude.
Simple mode is one song description. Custom Mode splits the work. Style describes the world of the track. Lyrics carry the words, section labels, and a few local cues. Exclude names unwanted instruments, genres, vocal traits, or textures. Title is a short name, not a second prompt.
Field mix-ups can make your intention harder to follow: genre tags dumped into lyrics, “no guitar” written inside Style, or a title that tries to describe the whole arrangement. Put each instruction where it can do one job.
Suno documents detailed natural-language Style instructions and an Exclude field for unwanted elements. Treat those as the dependable controls. HOME keeps the same four parts together so you can copy them into Custom Mode without rewriting the idea.
Take a Simple mode description you already like. Split it onto four lines labeled Title, Lyrics intention, Style, and Exclude. Nothing should appear in two places.