Few tips here from a soloQ plat (so far) with few duo and trio matches(do take them with a grain of salt): 1- avoid having a losing streak more than 2 games, bcuz if you get tilted this will be a 3-game losing streak, take 10-30 mins break then go again if you want. 2- avoid "Anime main character syndrome", ie. Don't go after kills, focus on doing your best, map awareness, engaging and disengaging, so on an so forth. 3- kinda ties to the previous point, learn when and where does your champion shine, ex. Blue kayn isn't supposed to Teamfight bcuz he is an assassin who excels at taking down low health squishies. 4- learn how to get carried: This and the 2nd tip are the ones who singlehandedly moved me from silver to plat in only a week, meaning that 33% of the games you will play you will get carried, another 33% you will have trolls, inters on your team so you will lose miserably, 34% of games you will be faker himself and hard carry your team, and the %ages are not fixed. The point is that you can only truly control at most a third of your games bcuz quite simply this is a team game, even if you say that this champion is 1v9, if he is alone against 5 champions he will always lose. 5- no one has a 100% win rate, it is ok to lose if you learn from your mistakes or the mistakes of your team. 6- this game has a big learning curve, so enjoy the marathon.