General:
* Neat
* Orderly
* Clean
* Spick and span
* Immaculate
* Well-kept
* Presentable
* Shipshape
* In order
* Trim
More formal:
* Methodical
* Systematic
* Organized
* Arranged
Informal:
* Slick
* Polished
* Put together
Specific to clothing:
* Smart
* Crisp
* Sharp
* Dapper
The best synonym will depend on the specific situation and the tone you want to convey.