http://www.employees.org.uk has two menus in the left column.
I want the bottom one to float down the page as the reader scrolls-down.
I want simple, short, elegant coding for a DIY web author to understand.
This code is probably available for free on the net but all the examples I have seen are too long and sophisticated.

Code in the heading for one page is fine; I'll learn how to put it in a separate file to be called from all pages.

I don't mind if this is written in Javascript or anything else.
I don't mind if a big proportion of old-fashioned browsers can't float the menu down the page, as long as modern ones can.

Please contact me if I can explain better, but the problem is of someone who knows how to write HTML and HTML tables but doesn't know how to make one of them float.