How to lose a ranked game?

All right so I went solo que ranked and did everything I let someone take my lane even tho I called first, and his lane lost as usual, I followed everything in all guides which are all 100% totally useless I even watched the video guides on youtube but I survived and played ranked and won again, I played meta, I tried Katarina ap mid, Yasuo with Statik Shiv, invincible Master Yi, Invincible Riven, I always take flash I DID EVERYTHING. So how do you do it ?