A long-distance bridesmaid may feel out of the loop if she has to miss showers, fittings, or planning sessions. Help her feel like she's still a part of the wedding with jobs she can do remotely. Here, four tasks she can take on no matter how far away she lives.
As long as she has time and an Internet connection, she can take a look at the bride's Pinterest boards to get an idea of her style direction and start contributing ideas for venues, flowers, stationery, bridesmaids' dresses, readings—pretty much anything she'd do if you two lived in the same town. While she won't be able to actually scout locations with you, she can certainly search for farms that are rentable for parties, or white flowers available in March, or whatever else that's pertinent to your wedding. Ask her to FaceTime you her findings (as well as send an email with details) so she can get your reactions and feedback visually.
If your long-distance 'maids is creative and detail-oriented, ship necessary favor materials straight to her home with directions for putting the little gifts together. Since she won't want to spend all her free time making 127 elaborate favors, keep the project simple, beautiful, and worthwhile. (Note that edible favors rate well with wedding guests.)
When you find out your church won't permit Chloe, your beloved dachshund, to walk down the aisle as your flower dog, you're going to need a sympathetic someone to listen to you cry. Your faraway bridesmaid is the ideal person to schedule a long chat with. (You'll feel more of the love from talking rather than texting your disappointment.)
Besides being there when you have problems, she'll also want to be there when you don't. She should call, text, or email you regularly to let you know she cares. She can start a private Facebook group for the bridesmaids to stay up on the latest developments. Even if she can't be there physically during planning, her presence will still be felt.