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15 tips for AdWords beginners [webmasterworld.com]
As I said I am an affiliate linking to another site which is not mine so I cannot add adsense.
No, you didn't say that. You said you promote Clickbank as an affiliate. As it appears you are now saying you don't have your own website, you just put the affiliate link in your Adwords ad, is that correct? If that is the case you really should study the merchants landing page very well. And start a thread about this in the affiliate forum. People there can perhaps help you better with your question because Adwords might not be the problem.
My advice; no one's going to hand you the holy grail you gotta find it for yourself. That's the nature of the Google Cash game that I assume your playing. Profitable products can be as rare as hen's teeth so when you find them you keep them to yourself and milk them for all they're worth while you can.
Try this; if you're promoting predominantly Cbank products there is some useful free software that you can use to identify new products and study ranking trends. Pick things that are fairly new and trending up. Pick an assortment of different products and set up ad campaigns. If after a decent amount of clicks the product is showing a loss (I suggest 300-500) get rid of it and try something else. Though some of these could come good after a little more time I think it's best to be ruthless with your culling. When you find a product that converts, ramp up your efforts & refine your campaign to maximise profits. Over time you learn which niches work best for you.
All the best.
I cannot find the affiliate forum.
If that's the case you better stop spending money on affiliate marketing for a while. First find the affiliate forum (I'll give you a hint: it's mentioned at www.webmasterworld.com/home.htm), do some good and long reading and then tweak and activate your campaigns again.