Ambika,
Xpath doesn't need to start with the first tag which is Html.
In general, every element has a unique id, you can start writing xpath pointing to that ID.
If any element doesn't have the ID, then write xpath pointing to the nearest element which has the ID.
Also do explore how to use css, which will be much faster than xpath.
Thanks
Murali
in Firebug I am able to find absolute xpath which starts from //html.. which is not healthy to use in general. Is there any other xpath and how to find that in firebug?