The key factor in the successful promotion of products is the ability to track and test your results.
If you can identify which ads or promotional methods are producing sales (as opposed to just website hits) then you can discard advertising that is not working and run more ads that are making you profits.
ClickBank provides an option to append a tracking code to the affiliate hoplink but if you want to carry out extensive tracking the ideal solution is to use an ad tracker.
Check out the tracking programs here in particular AnyTrack which integates with ClickBank sales notifications