Sign a written contract. Whatever agreement/understanding you have, ensure to keep a record of it. This would help you in case of any misunderstanding/dispute. Confirm the timings with the photographer of your day/night functions. Share the must-have shots that you want with your photographer in advance.For example, jewellery shots, getting ready shots, lehenga shots, bridesmaids pictures etc. Hand out a list with the names of the most important people to be clicked.