I have not been a member that long, but from my experience so far with ClixSense I think that there are only two ways to earn any money with this. When I say earn money, I am talking about more than a few dollars a month. If you stay a regular member, you will only have about five advertisements to click a day and you will earn $0.01 and $0.02 for a click. You can probably understand that this is not a lot during a month, even though you do this every single day.
But if you upgrade to a premium member, a $10 one time fee, then you will get a lot more ads to view and they pay you more to view each ad. At the moment there are 525 ads for premium members only, so I think that this is an option if you want to earn more money with ClixSense.
You can also earn money by referring others to ClixSense, and if they upgrade to a premium account, you will earn even more. A combination between upgrading to a premium account and referring will be the best way to earn at ClixSense. I have talked to several people who have been paid, so it seems that this company is legit and is run by people you can trust. I don´t have any experience with them, just what I have heard and the pictures of the cheques that I have seen.
The best thing about ClixSense is that it´s free. It seems that most people are looking for a way to earn money without spending any, this seems to be one of the cheapest ways to do it. You don´t have to spend any really, but I do recommend that you upgrade if you are planning to earn more than a few dollars a month. But that´s just what I think.