After Losing 5 games straight today
I am realizing that the one common factor between all of them was the way people handled losing.
TLDR at bottom.
What I mean by this is not being good sports or whatever. What I mean is people have this thing in their head where they keep hearing "the game is so snowbally now" and they just GIVE UP the moment one thing goes wrong.
They start chatting about how it is over and X or Y is unbeatable. They worry about being the victim, not what they can do to create comeback opportunities.
Instead of buying Merc Scimitar 3rd item vs the Warwick, the Lucian will buy more crit and complain about getting ulted. Instead of warding the jungle entrances and watching his minimap, the Jungler Graves will try to invade and get killed alone in the dark.
Instead of giving up the t2 and turtling under the inhib tower to wait out baron, the toplaner will try to dive in and start fights.
Don't give up untill they are IN your base. Ward up - AND I DON'T MEAN IN THEIR JUNGLE. Ward your jungle entrances. Ward one side of your lane and hug it if you are mid. use abilities to check bushes if you can.
Ward up, look for picks.
NEVER BE CAUGHT WITHOUT A CONTROL WARD.
THEY LOOK LIKE THIS: 
Get what farm you safely can, and above all JUST DON'T DIE.
TL:DR - Quit crying when one thing goes wrong and think of ways to slow down their snowball so it eventually stops. that is part of League of Legends.