There are 100 tips that could go here, but rather than insult your intelligence with things like "don't have a hangover on your wedding day"... I'll stick with a few good ones you may not have considered.
Where you get ready, DOES make a difference. If your preparations are being captured, it's important to choose a place that lends itself to great photos and video. Whether you get ready at a hotel, or at home, or in a venue bridal suite (many have beautiful spaces for this!), you'll be looking at this space for the rest of your life in your photos and video. The top 3 criteria are: 1. An area that is spacious enough. 2. An area that is NOT cluttered! 3. An area that has windows and natural light, the more the better!
Look at your fiancé As you begin your processional down the aisle, it's easy to become overwhelmed. ALL eyes are on you, as well as cameras. Resist to temptation to look down, resist the temptation to look at our cameras, and make eye contact with your fiancé. You can look around at guests a bit, or glance at your father or mother walking you down... This is a huge moment for you all! But when in down where to look, look directly at your fiancé, and smile. Finally, this is it!
Stop for a kiss! After you're married and you've been officially introduced by your officiant, everyone will be cheering- it's time to walk back down the aisle, as husband and wife... Take your time, and about halfway back up the aisle, STOP and share another kiss. If it feels silly because you've already kissed, trust me, this one will look more spontaneous, and less forced. You'll be posing for photos with your photographer all day... This is more in the moment, and it's literally surrounded by your loved ones. It makes for a great Photo/Video moment!
Don't chew gum Yes, I know this one seems self-evident, but sometimes we all like to chew gum, and it's easy to forget. There is no removing it from video if you're chewing as you walk down the aisle.
If you have any questions, don't hesitate to reach out! Best wishes!