Keep it simple: clean the fabric the way the product tag suggests, and do not use harsh cleaners.
For chenille or performance fabric, a soft damp cloth is usually enough for daily spills. If it is genuine leather, condition it about every six months so the surface stays soft, especially around the areas that move when the sofa extends.
For the power function, keep the track and hinges clear of dust, crumbs, pet hair, or anything that could block the movement. Plug the sofa into a wall outlet when possible, and do not force the sofa open or closed by hand if it feels stuck.
With normal care, a quality power sofa bed should handle everyday sitting, lounging, and occasional sleep without adding much maintenance.