"what are the best tricks to promote a website."
Search engines become more and more agile, crafty, innovative in tweaking their algos to eliminate the effectiveness of any "tricks". Thus effort, time and financial resources, spent on tricks may prove a waste very quickly - often the tips offered by SEO gurus are already obsolete.
On the other hand people become more and more skilled in avoiding the promotional/excess/useless portions of web pages, emails, etc.
Thus, the only "working" trick is great content - content that solves someone's pain or is about your visitor's passion. Of course, you should work to make it easy for the machines to figure out the semantics of your content and help people find the information that would be of value to them, so some SEO tweaking will be in order after all.
But as you probably know, the results of these efforts will not really be swift.
If you expect such - targeted advertising (e.g. Google AdWords) is the obvious way to go.
There really are no shortcuts.
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