If your internet is not stable, don't play!!!
I had just queued up, we were chatting in select, talking about roles when the client tells me that i have been disconnected. A second later i connected again. I have very stable internet, i can count the outages i had in the last 3 years on one hand. A minute later i dc'ed again, again just for a second. I told my team sorry and dodged. Then i called my ISP to learn that my whole area was affected and that i could have spotty service until tomorrow morning.
Guess what: I am not gonna play league until they have fixed their problem. And this is what i expect from everyone! If you start lagging or if you dc, even if its just for a short time, find out the problem before you queue back up. Especially for ranked but also for normal games. IT'S COMMON COURTESY! You are gonna play with four other people who rely on you being there for the entire game. Don't waste their time.