Ceremony rehearsals are one of the aspects of planning which can really impact the day of the wedding and help it run much smoother. Some wedding ceremonies are small enough or simple enough that they don't require a rehearsal. If there is no wedding party, or if only the couple is processing down the aisle in a clear path, you may be able to get away with not having one. Many weddings, however, are a little bit more complicated than that and having a rehearsal will help make sure everyone knows how to get from Point A to Point B, without any hiccups.
The main purpose of the ceremony rehearsal is to make sure everyone processing and recessing (aka, walking down the aisle to or from the ceremony location) knows where they are going and how they are getting there. Common elements that should be covered at rehearsals might include some of the following:
Seating: If parents and/or grandparents are walking down the aisle, they need to know where to sit after they give you a hug and kiss (or, you know, a high five if that is more your thing). While traditions and various religious practices have each family sitting on a specific side, I prefer that each respective family be on the side opposite of their child so they can see their face during the ceremony, rather than their back. Whichever side you end up standing on, make sure your family knows which side they should take a seat on after processing down the aisle.
Wedding Party: Another important aspect of rehearsals is to go over the spacing and location of your wedding party. It's important to come up with an order of how everyone will be entering the ceremony. There are so many combinations and one is not more correct than the other, but you do have to pick the order and stick to it so everyone can practice the same way it will be executed on the wedding day.
Officiants: Once again, no right answer, but you need to decide if the officiant will be processing down the aisle, or if he/she will already be at the front. If the officiant is using a microphone, make sure they turn the microphone to face each one of you during your vows, so your guests are able to hear you. Oh, and they should practice taking a big step to the side during the first kiss (I've seen far too many officiants photobomb the first kiss).
Readers: Anyone reading a passage or quote during the ceremony should also be at the rehearsal, even if they are not processing down the aisle. Most often the officiant will take a step back and allow the reader to stand in their place. If you have multiple readers in a row or within a very short period of time, it may make sense (depending on the space) to have a separate microphone set up for the readers to the side. Ensure the reader knows the cue for them to stand up and head to the microphone. Also, readers should be seated in the first or second rows in an easily accessible seat to the front.
Rings: Make sure whoever is holding the rings (traditionally the best man/best person) knows their cue to hand them off.
Music: Make sure your musician or DJ knows when to switch the songs if you have multiple tunes during the processional.
Recessional: The most common and quickest way for everyone to exit the ceremony is the couple first and once they reach the end of the aisle, they should be followed by one person from each side two at a time from the wedding party. Opposed to the processional, where there is an even spacing between each person or group, the recessional can be continuous exiting. Once the final individual or couple of the wedding party has left, the parents should go next, followed by the officiant and then the rest of the guests.
What not to do: Do not read through the entire ceremony and your vows during the rehearsal. A rehearsal's primary purpose is to go over the flow and movement of everyone involved, not to spoil the ceremony the day before the wedding!
Each ceremony is as unique as the couple, so your ceremony might have an additional element not mentioned above. Make sure whatever the ceremony needs are, it is practiced at least once (ideally twice) at the rehearsal. The ceremony often gets overlooked, but this really is where the magic happens and will feel much more natural if everyone knows where they're standing or sitting and how they are getting there.
What is one aspect of your wedding ceremony you'd like to see covered in more detail in a separate blog post?