Lower the resolution
Reduce the frame rate
Use a more efficient codec
Lower the video bitrate
Use variable bitrate instead of constant bitrate
Shorten the video duration
Remove unnecessary audio tracks
Lower the audio bitrate
Use mono instead of stereo if acceptable
Trim unnecessary scenes
Crop out unused borders
Avoid excessive keyframes
Re-encode with compression settings optimized for size
Convert to a smaller file format
Remove subtitles, chapters, and metadata if not needed
Use two-pass encoding
Avoid duplicate copies and backups in large formats