How can I assure that the guests arrive on time and the service is on schedule?

There are several things you can do to ensure that your ceremony starts on time. One idea is to set the time on the invitation for a half an hour earlier than when the service is supposed to begin. This gives guests a half hour leeway if anyone is running late. You can also just write explicitly on the invitation that the service “will start strictly at 11:00 am and anyone who arrives past 11:05 may not be let in.”