Make sure the language is clear and easy, avoiding technical jargon where possible. Provide both beginner and advanced options so readers can choose based on their comfort level.

Also, mention the importance of saving in the right format. While the user wants a JPG, sometimes converting to PNG for lossless editing and then back to JPG at lower compression might retain quality better.

Another method is adjusting the resolution. If the image is used for print or web, the required resolution differs. Resizing might help if the original resolution is low, but upscaling can lead to blur. Maybe mention using algorithms like bicubic or Lanczos for better results.

Also, mention checking the original source for a higher quality image if possible. If the user has access to a better copy, that's the best solution. Otherwise, work with what they have.

Maybe include examples or case studies where someone successfully improved a JPG using these methods. Also, provide links to recommended software and tools for each step.