Harvey Segal says ...
If I had to give just ONE tip to web site owners this is the one
Are you spending time on big advertising campaigns ?
Then I order to you to stop now.
They will only bring you one-off spikes in your sales.
What you need to do right now, before anything else, is make web site changes which will squeeze that extra X percent conversion of your visitors into sales.
Once that is done then, logically, all your future traffic, for ever more, will also result in that X percent increase in your sales.
Learn how it's done, click here