Use a PDF compressor tool
Reduce image resolution
Compress images before adding them to the PDF
Remove unnecessary pages
Delete unused objects and metadata
Save the PDF as optimized or reduced size
Convert images to JPEG instead of PNG when possible
Lower the quality of embedded images
Remove embedded fonts if not needed
Flatten annotations and form fields
Use grayscale instead of color if acceptable
Recreate the PDF with smaller source files
Split large PDFs into smaller files
Use “Print to PDF” with lower quality settings
Remove duplicate content and blank pages