How do I reduce file size for Personal Library uploads?

As there is a limit to the storage space on the Personal Library it is a good idea where possible to reduce the size of files you need to upload.

For Microsoft Office files there are a number of options which are described in this article: http://bit.ly/1gZQLZ6 

For image files the options are described in this article: http://bit.ly/18BRA6M

Another option is to compress one or more files into a zip file: http://bit.ly/19qqTSc