Your Wedding, Your bridesmaids.

Make it a girl's day out!
Pick a day when you and your bridesmaids can all go out and visit your favorite bridal shops.
Have a specific idea of the kind of dresses you have in mind. Have your bridesmaids try on several dresses and share opinions. Made sure the style you select is complimentary for
all your bridesmaids.
Make it a very fun experience and then pick a place to have lunch and maybe some drinks.