You need to save the changes you want into the Normal.dot or whatever
template you are working on.
The following has instructions how to find and modify the Normal.dot. Be
aware this also has instructions for other problems which you are not
suffering from so please ignore portions of this document.
You can always make the changes to syles and have these saved into the
template from your document.
Make the necessary changes using Styles and Formatting, modify the styles
and then check the box "Add to Template", this will update the Normal.dot or
whatever template the document is based on the next time you save your
document. The next time you open a new document based on that template, the
changes should be present.
Hope this helps
DeanH