I know this seems like such a silly wedding planning idea but you'd be surprised at how many couples miss the center mark in the midst of all the emotion! You have this beautiful arch or stunning backdrop to your wedding ceremony, now don't you want to make sure you stand in the middle of it?
In the midst of all that is going on during your ceremony the last thing you're going to remember is stand in the spot that puts you and your groom in the center, so do your self a favor and mark the ground with washable paint or painters tape. Make sure to check with sure the venue is ok with your markings.
Its as simple as that, and trust me it will be worth it.