Adjust skin gloss, skin details, improve hand and tooth details, add character appearance data, material details, background..etc..
Recommend
Steps :30~50 (Testing with step 50 and DPM 3M++ SDE Exponential gives quite good results)
CFG : 7
You can also use hiresfix or After Detailer
Sampling : DPM 3M++ SDE Exponential , DPM 3M++ SDE Karass, Euler a or DPM 2M ++ SDE Karass
Nprompt:
(worst quality, low quality, illustration, 3d, 2d), open mouth, tooth,ugly face, old face, long neck,