Don’t go overboard.
As fun as they are, too many transitions can be distracting and cause your video to look amateurish. It’s best to stick with a few well-placed transitions than to crowd your video with too many effects.
Keep your transitions consistent.
Too many different transitions can make your video seem unevenly paced and erratic. Pick a few types of transitions to rotate between and you’ll establish a consistent flow your audience will get used to.
Use them where appropriate.
Think about how your transition serves your story. A transition that marks a new chapter or phase of the film, such as an intro or outro, will be more expected than a transition between two clips in the same scene. Your transitions should be a storytelling device, not a way to simply fill space or add flashy effects.