Google Adwords SUPER Tip #10...
USE MULTIPLE AD GROUPS, EACH WITH FEW KEYWORDS
This is probably the most important tip. There are MANY reasons for this advice - we won't go into them now.
Simply follow it and benefit from the added response - and lower cost per click.
Break down your keywords into small, tightly themed groups - and put them in their own Ad Group.
You can have multiple Ad Groups, each with a few (or even one single) keywords.
Turn Your Ordinary Business Into A Cash-Flow,