Narrative/Plot

Choose a narrative to build your show around. This can be as simple as 'time passing', but there are other ways to do it. If you have multiple subjects, tell each persons story in order, or follow one person into a big event, and another person away from it. Remember, the story is what actually happened, the plot is the way in which you choose to tell that story.

Music and Sound

Use music to establish the proper mood, something that’s appropriate to the theme of the events. For a slideshow that covers a whole year, Vivaldi’s Four Seasons is a composition that is evocative of the different quarters of the year, iconic and timeless. Or for graduations, remember Copland’s Fanfare for the Common Man.

Don’t forget, too, that the sound function can be used for things other than music. As long as you have a microphone, and recording software, you can add narration. You can also find other sound effects on the web to spice up your slideshow.

Effective Effects

Don’t overuse the effects. Think of each picture as a story. Identify the key elements in that picture, and find the best way to reveal them in the best way — in other words, to tell that story. Picking the right effect, and the right transition between photos, will help you tell that story in the best way. Overusing the effects can distract from your message.

Titles

Your slideshow will need opening and closing credits. You should also use titles/captions to identify major sections of your slideshow or anything else that you think the viewer might not understand. You can label locations, people, events, dates, objects, animals, and more. Stay away from unnecessary labels. A horse is a horse. No need to label it unless the viewer will have some trouble understanding the context. Funny labels can work but you need to be consistent throughout the slideshow.

Pacing

Pacing is essential. People typically only need about 5 seconds to take in a photo, so 12 pictures per minute of show is Photo to Movie’s oft-expressed rule of thumb. But playing with that can be a fun way of building excitement. For earlier, or less important events, a slightly slower pace makes it feel like the beginning of the journey. As the action heats up, make it faster and faster. A big finish might be a really quick review, at 2 or 3 photos per second, of all the pictures you’ve used in that part of your slideshow.