You are the key to making the memories of the graduating student sempiternal. You have the skills; you have the camera; all of it is you. I know that this puts a lot of pressure on your shoulders, but it's honestly not that bad. As long as you are prepared and great with acting like paparazzi, you should be fine. But in all seriousness, do not feel so much pressure that you miss gratifying moments. You are the professional; you know what to do. But here are some tips for you to double check just to be sure.

Some venues have lens restrictions. Venues such as sports arenas and concert halls are the most typical ones. High schools and colleges are different, though, so if the graduation is hosted there, you are in luck! My particular graduation is at Ford Field, and they have a 5 inch lens limit. While that sucks, as a photographer, you should be okay with working around that. That just means you have to get up, move around, and get as close as you can. You can no longer rely on long lenses.  

There are many types of photos that can be taken on graduation day. These include family photos, the graduation ceremony, the graduate individually, friends, photos before/after/during the event. Get a clear picture of what is required of you and go forward with it. It helps to know this stuff beforehand so that you can make a plan and think of all of the photos you want to get. But also, do not forget to get the cliche shots: a formal shot of the graduate with his/her diploma and a classic "tossing-the-hat" shot.

This is pretty important for almost all types of photography. You should always shoot with an intended story or meaning. This is especially important for a graduation. These photos should be cohesive and tell a story of graduation day. Nobody should be left confused after viewing the pictures. 

Details make events and days and memories. Don't forget to capture these! Get a photo of the cap and gown, chords, and diploma. the tassel. Be creative and see with your photographer eye.

Get the candid shots during graduation. Get the shots that most people do not think of capturing: during the speeches, when the graduates are walking in/out, etc. These are shots that your client will love. You may even capture a great moment that they did not see for themselves. Always have your camera ready because you never know what may happen.

It is crucial during any photoshoot to know the gear you are working with, inside and out. During graduation, you will not have time to fumble around and "hope for the best." Moments pass by so quickly, and you do not want to miss any important ones.

Most graduation venues have horrible, horrible lighting. I hate indoor venues just for that reason. {Luckily mine is outdoor, which can present its own challenges when you have limited shade.} Although you do not want to bring your entire camera collection with you, make sure you have the right gear so that you can combat the lighting issue.