Empty the Trash
Delete large files you no longer need
Remove duplicate files
Uninstall unused apps
Clear Downloads folder
Delete old iPhone/iPad backups
Remove large email attachments
Clear browser cache and website data
Delete unused disk images and installers
Remove old media files
Move files to external storage
Use iCloud Drive to store files
Optimize storage in Apple menu > About This Mac > Storage
Delete old Messages attachments
Remove unused language files
Clean up desktop files
Review and delete large files in Storage Management
Restart your Mac after cleanup