They appreciate no vulgarity. The concept of vulgarity is very extensible depending on the country, so this paragraph requires clarification. What may be acceptable in Russia often seems vulgar in France. Too short skirts, high heels, extremely deep cleavage, transparent blouses, sparkles and rhinestones on all clothes - all this is considered to be attributes of the representatives of the oldest profession. Therefore, if you walk down the street of Paris in a scarlet mini-skirt, in boots on a stiletto and a shiny blouse with a neckline to the navel, do not be offended if you are whistled next.
Be as natural as possible - in clothing, makeup, and hairstyle.
Do not worry about being special. All girls themselves are different from French women in any clothes, so there is no need to try to stand out even more. And very few French people love aggressive combat makeup. Be as natural as possible - in clothing, makeup, and hairstyle. If you do not know for sure what your cavalier loves, then your style should be as simple as possible, it is the right way to make him like you.