I came across this article and thought it had some helpful hints. Really though, the best hint I can give is talk to your photographer. Tell him/her what you have in your mind, and make sure they share their vision with you. You want to make sure that their vision fits your family. (If your family is country/western, you don't want a rock and roll shoot.)
1. Discuss the family portrait together with the entire group and your photographer. Your family portrait should convey a sense of your family's personality. Talk about possible color schemes, settings and poses.
2. Choose clothes that fit with the setting of the portrait. If you are having your portrait taken on the beach, summer clothing is appropriate.
3. Coordinate colors. Everyone in the family portrait should wear colors that meld well together. Some families choose to match their colors exactly. While this is not necessary, you do need to ensure that all the clothing colors complement each other.
Here are some examples of melding colors:
2. Choose clothes that fit with the setting of the portrait. If you are having your portrait taken on the beach, summer clothing is appropriate.
3. Coordinate colors. Everyone in the family portrait should wear colors that meld well together. Some families choose to match their colors exactly. While this is not necessary, you do need to ensure that all the clothing colors complement each other.
Here are some examples of melding colors:
Here is a color wheel that helps mix and match colors. I've also included the link that goes along with it.
4. Avoid different shades of the same color. If one person is wearing a bright red shirt, you don't want another person wearing a light red shirt. It will just look like you attempted to match but didn't quite succeed.
5. Choose neutral or muted color tones. Bright colors tend to draw the eye away from the subjects. However, bright colors make for great accessories (think shoes, jewelery, etc.)
6. Coordinate the style of clothing as well. Everyone should be dressed in a similar style, such as formal or casual.
7. Avoid stripes, plaids, logos and bold patterns as they will draw attention away from the faces in the photo. You want the main focus to be on your family, not your clothes.
8. Pick clothing that fits nicely. It should be neither too tight nor too loose. The clothes should hang on the bodies well, without folding or creasing.
9. Consider clothing that covers the knees and elbows. These areas don't photograph as well as the rest of the body so it may be wise to choose clothing that covers them.
* Talk to your photographer before the shoot if you feel you have "problem areas." I once had a client who thought she had a fat neck, so she wore a turtleneck to cover her "problem." In the photos the clothing made it look even worse. To distract from her neck, a v-neck would have made a better choice to elongate what she thought looked "fat." There are many poses and camera tricks a photographer can use to camouflage a problem area.
10. Avoid trendy styles. Basic classics are better clothing choices for your portrait. Trends pass and you want your family portrait to be timeless.
11. Bring a few back-up clothing choices, in case anyone experiences a last-minute spill and needs an emergency replacement.