League of Legends, like most competitive online games, can be really tough if you are playing it seriously. Going up the competitive ladder can be a really frustrating task, if you are like me and don't know the small details of the game that are important to win matches.
And while we are dying to make it to the diamond rank in LoL, it is important to keep in mind that this is not an action game, it is a competitive game that requires strategy. I learned this the hard way. Luckily, I found a decent guide to hep me understand the ranks and has important tips helped me improve and rise in the ranks. A bit though, you still gotta git gud.
May be you can get higher, good luck