Easiest way to go to your previous location in a large word document

Question

I make regular small edits to a 150 page document and find it frustrating that word does not remember what part of the document I last edited. Is there some option I can set in word so that it does remember, or if not, can someone suggest an easy trick to help with this problem.

EDIT: The document is divided into a great many chapters and sub-sections and sub-sub-sections. Any tips on quickly jumping around from section to section would go a long way to helping with my problem. In outlining mode, with all the outlines closed, jumping around the file is a joy... but very irritatingly, when word is shut down and re-started, it opens all the outlines. So at the moment, at the beginning of every editing session I manually close all the outlines, then I can more easily navigate to the part I want to edit. This feels very clumsy, especially if all I want to do is add one sentence somewhere.

Answer 1

Answering my own question... I've just discovered that I can close all the outlines in one shot by clicking "Show Level 1". This means I can jump to whatever section I like pretty quickly. Using a bookmark as suggested by "random" is useful too.

Answer 2

During an editing session:

Undo then Redo.  

At the start of an editing session:

Shift+F5

Note the latter may require an edit to Normal.dot.