The costume is only a ninja outfit, not a uniform. I think it's possible to recreate both a ponytail and a Hair down.
In the image used, the character is wearing dirty clothes, so if you want them to wear clean clothes, I recommend using words that evoke stains or torn clothes, such as 【Dirty,torn】as your negative prompt.
Hair color is difficult to recreate, so it might be effective to use words like 【【brown hair,light brown hair,black hair,blue hair,orange hair,blond hair】as your negative prompt.
【base】
dark brown hair,long hair,straight hair,ponytail hair,asymmetry bangs,swept bang,ibbon hairornament,pink ribbon,hairclip,flower hairornament,sidelocks,dark gray eyes,narrow eyes,mole under eye,
【Ninja clothes】
ninja costume,white Kimono,white choker,Sleeveless,white elbow gloves,pink trim arm guard,,lightred arm band,navy Obi,hip long fabric ornament,mini skirt,leg guard,white thighhigh socks,pink trim leg guard,lightred ankle band,zori,
