We all want our photos to look the best on the forum, and we want to be able to share them with other members. The following is a demonstration of a quick, simple workflow to save your photos in a manner that preserves their appearance while making them fast loading...1) Select
Image->Resize 
2) Set the Pixel Dimensions section to Pixels, rather than Percent, and adjust to the required size (remembering to keep it to no more than 700 pixels on the longest side). Make sure the Resolution is no more than 72 pixel/inch (anything higher makes the image slower to load, but no better to look at)
Make sure Resample is selected. The Smart size resampling method seems to give the best results.
Click OK.
2) Select
File->Save As. Choose jpeg. Don't click save (yet)!
In the bottom right there is an
Options... button. Click this
In the bottom right of the Options dialog there is an
Run Optimizer... button. Click this
4) A new dialog appears. On the left is the original image. On the right is the web version of the image that you're creating. You can pan and zoom these previews. Change compression up and down to see overall file size/quality. Note: You can zoom in on the pic to around 120% or 150% to see artifacts etc.
It's a good idea to click the
Save Exif data option
Above the Quality / Format / Download Times tabs you can see the original file size and compressed file sizes. Adjust the compression % to get a suitable file size.
A handy feature is the Download Times tab, which provides estimated load times for the image.
Of course, if there are multiple images to load, the times need to be added up!
5) Click
OK and you can change the filename & location.
6) Click
Save to save. Upload to an online image host and you're done!
Thank you to Ecniv for help with the Paintshop Pro workflow 
