In my experience, there is no one system that predicts winners consistently. I think most people who succeed at winning more than they bet have multiple systems they favor. The trick seems to be in setting a betting budget you can live with that lets you bet a worthwhile amount of the candidate numbers you've chosen.
I can't claim that I've been successful at that, but I do know there are posters in this thread that post winners in advance of draws fairly often. You might want to read this forum for a while, find posters you find being successful and start betting along with their predictions.
There's also another section of this forum called Lottery Systems. There, people post any number of methods to predict winners, usually by applying addition/subtraction methods to previously drawn numbers. My advice would be to look through these and backtest the methods that sound interesting to you either on paper or in a spreadsheet. Whatever you do, test it out first, before spending money.
There's also tools on here in the Premium Features section that can help you decide on what to play. Full access to those tools is limited without subscribing for a fee, but you can test at least some of them out for free to see if they might help you.
If anybody offers to sell you predictions for a fee, those people don't have your best interests at heart. Lots of good advice on here for free but sometimes you just have to be patient and pay attention until you find the right mix of tools to help you succeed.
Best of luck always!
OhSoClose