As the irrepressible Tom Cruise once waxed lyrically about “show me the money”… to do so in PPC you need to balance the volume of ppc traffic with negative keywords.
If implemented correctly negative keywords will improve click through rates (CTR’s), improve Quality Score (QS), reduce cost per clicks (CPC’s) and thus deliver higher ROI/ reduced costs i.e. improved Return on Ad Spend (ROAS).
Without negative keywords you will be paying for too much irrelevant traffic that will impact your campaign in the long term if not nipped in the bud (from a cost and QS perspective).
In a nut shell you should:
1/ Add as many obvious negative keywords before the campaign goes live
The easiest tools to use for this are common sense and the negative keyword tool in Google adwords however other tools including Wordstreem, Wordtracker, Spyfu and Google suggest can be used to supplement and refine your list. If you’re an agency you might already have a negative keyword list for that sector you can adapt and it s always advisable to scour the tinterweb for assistance e.g. a basic yet good B2B thought provoking list has been created by ko marketing.
2/ Refine and update on a regular basis
The negatives should be updated on a regular basis (advised: weekly basic review and a root and branch review once a month) by weeding out those clicks that are clearly irrelevant or those that are simply not converting.
You can add negatives at an ad group or campaign level and with there being a case for both I will leave that discussion to Denver PPC.