>>8693554
Generally I do it in two passes with
>DPM SDE 40 steps, 1.5 latent upscale, 1 denoise, tile CN 0.35 strength 0.75 guidance end
>DPM SDE 40 steps, 1.33335 latent upscale, 0.85 denoise, tile CN 0.85 strength 0.9 guidance end
Fiddling around with the values depending on the style.
Sometimes I do the second pass with 25ish steps using multidiffusion at 0.45 strength.