Guideline
1) Find relevant but less popular keywords, i.e. profitable niche keywords
2) However, the best keywords area likely to be the most common names of the product. They sometimes have low CTR and are expensive
3) Identify the principal characteristics of your product. It is essential to create a coherent campaign answering what the customers are looking for.
4) One effective approach has been actually to spam keywords. I believe that more keywords can be used at the beginning and that these may be adjusted later after the first experimental period.
5) Use Google Preview Tools to get the most accurate results
https://adwords.google.com/select/Ad...ingPreviewTool
Learn from Competitors
1) Competitor’s Meta-Tag
a. Type in your main keywords and pick up a few important Adwords competitors
b. Go to their websites – right click anywhere on the main page – click “View Source” – press “Ctrl + F” to search for “meta name="keywords"”
c. Not all of their keywords are relevant as your business is not exactly the same
2) Competitor’s Adwords
a. Type in your main keywords and pick up a few important Adwords competitors
b. Use keyword generator to get a long keywords list and check whether your
competitors are also advertising these keywords
c. Watch them for 3 weeks and if competitors keep advertising some keywords, they are either making money on these keywords or they are
d. Use these keywords yourself to start your own Adwords
3) Alternatively
a. Use Google Cash Detective to auto identify profitable keywords from competitors
b. Then use Google Cash Automator to auto manage your Adwords to replace your successful competitors
Read The Complete Adwords Study Notes.