With a PPC ad, you have the option of running multiple campaigns. You can run one for broad keywords, another for the name of your product along with your name for branding purposes, and one that includes variations of long-tail keywords. You'll generally pay more for the broad based words, as most of your competition will be bidding on them as well.
You don't want to target irrelevant keywords because you have to pay for each click that goes through to your domain. Some people try using the bait and switch tactic, but it rarely produces viable results in the marketplace.
Instead of sticking to one and two word keywords, try developing longer phrases. You might be the only pay per click result that comes up because many marketers don't know about the power of scooping up lengthy phrases. The more specific your keywords are, the more targeted traffic and click throughs you will receive.
Dolls might be a good keyword to use for a broad PPC ad campaign, but adding a related word that makes it more specific (like Antique Dolls) brings a higher click-through rate.
The person who's searching for information related to antique dolls would click on an ad that specifies the word antique because dolls would be too broad of a subject.
Another broad keyword is 'credit cards'. Huge search counts, but also a ton of competition. But if you focused on 'gas rewards credit cards' you'll now have a specific keyword phrase that is laser targeted. Dig deep into whatever niche market you are doing business in and you'll find the goldmines just waiting for you to cash in on.
Use software to come up with the best keywords to increase your PPC success. Get a one day pass at WordTracker or download a tool like Good Keywords to get some brainstorming help.
Free versions are good to start with but usually have limited features. If you intend to use PPC as a regular source of advertising, you'll want to have a full paid version. Some of these software programs charge by the month and some it's a one time fee. Pick the one that's within your budget, and will do everything you require.
These tools will help you dig down for long-tail results that could pull in prospects to your ads. Software programs can also pick up on the spelling variations and mistakes for the keywords for your campaign, something you might not have thought of when creating your list. They should also give you the strength of competition for the keywords. You want huge relavent search counts, with as little competition as possible.
Visit your competitors websites and right-click on the page to View Source. You should see a META tag for their keywords in their HTML code. Grab those words to add to add to your list.
Take your time to conduct thorough research and find the best keywords to use for your PPC campaign. Track the ads to see if those keywords are performing. If they're not, pull the words and use a different set.