She always wears neat, tidy clothes.
I tidied up the room nicely.
綺麗 is a broader term for 'clean' or 'beautiful'. 小綺麗 adds a sense of modest, careful neatness rather than striking beauty.
Standard kanji spelling.
Variant kanji spelling.
Mixed kana-kanji spelling; sometimes used for readability.
Compound of 小 (ko, 'small, modest') and 綺麗 (kirei, 'clean, beautiful'). The prefix 小 softens the meaning to 'neat and tidy' rather than 'strikingly beautiful'.