None, because it's gambling, even your analysis can't keep you from losing, a performing soccer team today will fumble when you don't expect, you need to gamble with what you can afford to lose, don't believe that whatever you gathered is the accurate analysis and things will work out in the exact expectation.
Yes, it's true because no one always wins bets even though they have done an in-depth analysis of statistics and so on, even that still loses, so there is no best tipster, everything also requires luck, beginners must know about the risks of gambling, at least so they don't easily trust tipsters outside there which may be misleading especially betting on lesser known leagues.
Many major leagues such as the EPL, UCL and Bundesliga, including other major leagues, are safer from fixing, I've also heard of minor leagues that are less well-known, there are lots of fixing, so it will make it difficult for us to guess and bet even though we have analyzed it correctly. it's best to learn to research and analyze yourself is the right step especially betting on the big league is good enough.