1. It depends upon the skin color as to the filter's effect. Also depends upon what you are trying to achieve. Enhancing a portrait or providing some type of "interperative" special effect.(posted 8829 days ago)2. Try a #8 (yellow) first. This filter corrects panchromatic black and white film response so that the colors are translated into gray tones matching the actual color relationships. Blue is usually rendered too light with panchromatic black and white film, yellow filters blue.
3. Try a #11 filter (green / yellow). This filter looks green, but it actually has some yellow in it. This is the most popular "green" filter for portrait work. Usually used with men because it darkens the skin slightly, and makes them look more "masculine."
4. #15 filter is deep yellow (looks orange). This will lighten caucasion skin. Is sometimes used with women for a high-key effect.
After that, you get into #23A, #25, #29 in reds. These filters are really not that effective with portait work as the effects are just too extreme (unless that's what you want). #58, green, is a color separation filter and blocks all red, and most of the blue. This would be a special effect filter for a portrait.