Rather than picking one color and everyone matching - pick a color scheme to add fluidity to your portraits. If you are having a hard time deciding on a color scheme, then look at your home. What colors do you tend to gravitate towards? These pictures will end up on your walls; pick something that will go with the color scheme of your home. You can also base your scheme off of the season in which you are taking your photos. With that being said, also note that natural, earthy tones photograph really well - shades of browns, blues, earthy/rustic greens, and reds.
Avoid patterns. Depending on the size of your family, having one or two people be in a pattern that includes most of the color scheme can be fun. Too many patterns will end up being too busy resulting in the fact that no one will look at you, they will be looking at your clothes.
Don’t be afraid to accessorize. Accessories like belts scarves or jewelry can add personality and texture to your photos.
Think Classic. These pictures will be hung on your walls to be cherished for years. Choosing to go the simple and classic look will help give your priceless portraits a lovely timeless look.