A birthday carousel works best as a short story about the person. Open with a photo that is unmistakably them, add the date or the age on the cover, then move through memories in order and end on the celebration itself.
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9 birthday carousel ideas
A year in photos: one photo per month since the last birthday.
Then and now: a childhood photo next to a recent one in the same pose.
Things I love about you: one photo and one short line per slide.
The dinner: candles, glasses, the cake and the table, told across four slides like a supper story.
Inside jokes: screenshots and photos that only your friends will get, framed as messages.
Age in big type: the number on the cover over the best portrait.
Twelve little hours: the birthday from breakfast to the last dance, each photo with its time.
Gift unwrapping: before, during and after, close up.
Calendar circle: a month calendar with the date circled as the cover.