The official Word blog discusses how to fix a tricky formatting problem in Word — using a pre-defined heading style in a document but not have every instance show up in an automatically-generated table of contents. (By default, Word includes all instances that match existing heading styles in any contents table.) The solution on offer — copy the existing style and give it a new name while removing its status as a heading — is fairly neat, though it does have one disadvantage: if you modify the original heading style, those changes won’t show up automatically in the cloned style.
You can get around the problem of modifying the original style by doing this:
1. Create your original heading style. For arguments sake lets call it 'Heading 1'.
2. Create your new header style and call it 'Heading 1 - not indexed'
3. Modify it's properties setting 'Style based on' to 'Heading 1'.
4. Create your table of contents and under 'Options' remove the entry for 'Heading 1 - not indexed.
Any items formatted with the new style will not be indexed, but if you modify the style for 'Heading 1' it will be applied to both styles.
The other thing you lose with this "two style" approach is the ability to reference the current heading text in the header or footer. I use this to have the current document chapter name in the footer.
This doesn't work very well if you have page numbering. The numbering does not recognize the previous numbers if you switch styles - it will start over from 1. Note to Microsoft: This should be a right-click option on the heading styles. Other word processors use separate field codes for the TOC - you mark each entry that you want in the TOC. The entry isn't there by default just because it is a particular style. This is a much better system IMO. To summarize: TOC SHOULD BE SEPARATE FROM STYLES. I can't stress that enough. This would eliminate all the unwanted garbage that ends up in the TOC all the time.
@Helen: you can set the TOC in Word to use either styles or specifically marked entries. (Edit field - TOC - Options - "Build table of contents from": uncheck 'styles'). IMO styles is a good way to do it because it automatically updates the text used for the contents when that text is changed in the document.
The problem with this two-style solution is that it doesn't allow automatic numbering of paragraphs, nor the use of the style for the header/footer. Is it the only solution?