Keep your team motivated and encourage them when they do something good.

Few things in League feel better than making a squeaky clean play and seeing your teammates say "Wow Tali that W prediction was insane!" or something of the sort. It's always good to be friendly and kind to your teammates whether you're winning by a mile or things are looking a bit grim. Supporting your teammates both in-game and mentally is the best way to make new friends and to always have a positive attitude, and most importantly, have the most fun. Joking around is also a good way to bring and keep people's spirits up, including your own. Thanks for reading, and stay positive!