how to make money on mylot?

You have to be active, participate in a lot of discusions with good comments of course. Also you can refer a lot of people.

Welcome to myLot! Start by reading this link and make yourself aware of the Guidelines. The only way to earn in the discussion area is by being active and posting quality posts which are within the Guidelines. : http://www.mylot.com/o/mylot.aspx

Finishing tasks would indeed be a good option as you know how much you earn prior to doing the task. Commenting on or starting a discussion would earn you some money too, but how much you get per post depends on how well it's written. Don't make too many scam-like posts that on goes for a line, for example. After all, you should be able to earn tens of dollars every month if you are active. It's not too bad aye. Happy mylotting ;)