Illustrious merge/mix.

I typically used CFG 5-7, (6) works best for me.
A resolution of width of 768 and height of 1024 at 20 steps seems to produce the best results, but 1024/768 and other combinations work as well.

Positive prompt highres, ultra-detailed, absurdes, masterpiece, + optional artist/style tag(s) | absurd details, depth of field, photoreal, foreshortening, light rays, god rays, chiaroscuro, backlighting can add some flair.

Negative prompt I use:
worst quality, low quality, normal quality, lowres, low details, bad photo, bad photography,bad art, bad hands, blurry, pixelated,

+ optional artist/style tag(s) |
render, 3d, depth of field, 2d, signature, text, watermark, Stable_Yogis_Illustrious_Positives, Stable_Yogis_Illustrious_Negatives-neg, zPDXL2-neg, zPDXLrl-neg, These are good depending on what you're looking for.

Settings:

• Sampler: Euler a | DPM++ 2M SDE Karras | DPM++ 3M SDE (sometimes works well).

• Steps: ~20.

• CFG: 5-7, (6) for more best results imo.

• Upscaling: 4x-UltraSharp | 4x_NMKD-Siax_200k | Both @ 55 steps 1.5X for 1152x1536 end resolution.