1. Clean and check the debris inside the printer.
2. Make sure the printer is correctly connected to the computer.
3. Check if the ink cartridges are expired or nearly empty and replace where necessary.
4. Check if the paper-type settings match the paper used.
5. Change any faded, smudged or crinkled pages.
6. Test the printer by printing a few plain sheets.
7. Adjust the printer settings such as the contrast, margin and gap size.
8. Try to print a document from a different computer, if possible.
9. Check for any printer updates in the software settings.
10. Look for any dirt or debris on the paper tray as well as inside the printer.