If you've selected a dress style you love, don't feel limited to choosing just one color. Your bridesmaids can wear the same dress in (preferably two) complementary hues. Then your attendants have very different coloring—for example, one's brunette with olive skin and another's blonde with fair skin—this works like a dream. Make sure you see the colors side by side—in person—before finalizing your choices.
See, it works!
Bridget's maids wore the same J.Crew dress in one of two colors, plus hair accessories by Handle & Spout.