My Config for this Model:

Positive: illustration, Volumetric_Lighting, ultra-detailed, very aesthetic, intricate details, absurdres, 8k, masterpiece, best_quality,

Negative: photo, deformed, greyscale, disfigured, low contrast, lowres, (bad), text, error, fewer, extra, missing, worst quality, jpeg artifacts, low quality, watermark, unfinished, displeasing, oldest, early, signature, extra digits, artistic error, username, scan, [abstract], duplicates, tight, long_legs,

aspect radio: 5:8

width: 832

Height: 1216

first step: 28 (txt2img)

step: 18 (upscale)

sampler: eula_a

scheduler: karras

cfg: 5.0

rescale cfg: 0.40

upscale factor: 1.5

upscale denoise: 0.20 - 0.30

add noise: 0.10

upscale model: "4x_NMKD-Siax_200k.pth"

vae model: sdxl_vae

Have fun! :)