I guess playing more than a thousand games, recording them and looking for my mistakes, trying different strategies and stick to the one that works best and identifying the usual mistakes of other players and capitalize on them definitely helps. And there are a lot of clever tricks too what you can figure out again if you play a lot. Of course winning 3 games in a row means short term luck too and it is quite rare for me too. It definitely helped, that one of the games was with only 4 players.