woot!
noobs
1)
Don't save JPEG with MS paint!~ you'll be doomed!~ doomed!
2) If you edit an image, don't save it again and again as JPEG, since with each save you loss quality.
3) Use a good program
like
Gimp or
Image Magick
4) If your image is big, you'd might want to crop it down, no point in huge images.
5) You can control the compression rate as opposed to the quality, and no, just because it says 100 quality doesn't mean it's 100% quality.
[url=http://en.wikipedia.org/wiki/Wikipedia
reparing_images_for_upload]This[/url] page explains a lot about how to save images and gives a lot of good tips, like it's better to save certain images in PNG (images that have few colors, with large areas of the same color and sharp edges). Also it is a good idea, mostly, to use a pallet of fewer colors in such images.
And erm, that's it in a Nutshell
/ 
