Google Docs multiple Headers And Footers

For multiple headers (i.e. different header on each page) use the following tags.:

<div class="google_header">your_content_goes here</div>

For multiple footers:

<div class="google_footer">your_content_goes here</div>

Note that when using multiple footer, do not insert a footer using the UI. It will add the following tag to the page:

<div id="google_footer">your_content_goes here</div>

Setting the id to google_footer makes this header move to the first page, which is not what you intend most of the time with multiple footers.
For page number:

<span class="google_pagenumber">1</span>

For page count:

<span class="google_pagecount">1</span>

Please note that if you are using the page number tags, it would be best not to choose page number option in the user interface as that might conflict with the page numbers you have already entered.