Use a PDF compressor tool
Save the PDF as optimized or reduced size
Remove unnecessary images
Lower image resolution
Convert images to JPEG instead of PNG
Compress embedded fonts
Remove unused objects and metadata
Delete blank pages
Flatten annotations and form fields
Reduce the number of pages if possible
Export the PDF with smaller file size settings
Use “Save As” instead of “Save” when available
Print to PDF with lower quality settings
Split large PDFs into smaller files
Convert scanned pages to black and white if suitable
Use OCR only when needed
Remove embedded attachments
Compress the PDF with online or desktop tools
Recreate the PDF from the source file with optimized settings