Too often we assume we know what others want. Sure, we're right sometimes. But sometimes we're way off. So just ask the bride how you can help her. And don't wait until a week before the big day. After you've been invited to be in the wedding and you do a celebratory happy dance, have this conversation. It will help you both get clear on your expectations of each other.
Maybe she'd like help with the seating arrangement at the reception or look to you to throw a bridal shower. You'll never know unless you ask. Asking how you can help is an easy way to start off on the right note.